`cargo fix --edition-idioms`

author: Simon Sapin <simon.sapin@exyr.org> 2018-11-01 21:43:04 +0100
committer: Simon Sapin <simon.sapin@exyr.org> 2018-11-08 09:28:00 +0100
commit: 2012be4a8bd97f2fd69f986c8fffb1af1eec21dc (patch)
tree: c9f1ef91146253f72987cb1436866523880965e0
parent: b1fd6237d1304f3d57abdafd3e6e738c1ece9f83 (diff)
download: servo-2012be4a8bd97f2fd69f986c8fffb1af1eec21dc.tar.gz
servo-2012be4a8bd97f2fd69f986c8fffb1af1eec21dc.zip
203 files changed, 665 insertions, 1281 deletions
diff --git a/Cargo.lock b/Cargo.lock
index 75170722149..845335f733f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2925,13 +2925,13 @@ dependencies = [
  "heartbeats-simple 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "influent 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "jemalloc-sys 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.42 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "profile_traits 0.0.1",
  "regex 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.13 (registry+https://github.com/rust-lang/crates.io-index)",
+ "servo_allocator 0.0.1",
  "servo_config 0.0.1",
  "task_info 0.0.1",
  "time 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2945,7 +2945,6 @@ dependencies = [
  "ipc-channel 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "profile 0.0.1",
  "profile_traits 0.0.1",
- "servo_allocator 0.0.1",
  "servo_config 0.0.1",
 ]
 
diff --git a/components/allocator/lib.rs b/components/allocator/lib.rs
index 963ff5f759b..3ce50be8b22 100644
--- a/components/allocator/lib.rs
+++ b/components/allocator/lib.rs
@@ -10,9 +10,11 @@ static ALLOC: Allocator = Allocator;
 pub use crate::platform::*;
 
 #[cfg(not(windows))]
-mod platform {
-    extern crate jemalloc_sys as ffi;
+pub use jemalloc_sys;
 
+#[cfg(not(windows))]
+mod platform {
+    use jemalloc_sys as ffi;
     use std::alloc::{GlobalAlloc, Layout};
     use std::os::raw::{c_int, c_void};
 
@@ -96,9 +98,7 @@ mod platform {
 
 #[cfg(windows)]
 mod platform {
-    extern crate kernel32;
-
-    use self::kernel32::{GetProcessHeap, HeapSize, HeapValidate};
+    use kernel32::{GetProcessHeap, HeapSize, HeapValidate};
     pub use std::alloc::System as Allocator;
     use std::os::raw::c_void;
 
diff --git a/components/atoms/build.rs b/components/atoms/build.rs
index 245440b06e5..6cfdfe2e7d7 100644
--- a/components/atoms/build.rs
+++ b/components/atoms/build.rs
@@ -2,12 +2,11 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate string_cache_codegen;
-
 use std::env;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
 use std::path::Path;
+use string_cache_codegen;
 
 fn main() {
     let static_atoms =
diff --git a/components/atoms/lib.rs b/components/atoms/lib.rs
index c1da7167bde..87009b13b67 100644
--- a/components/atoms/lib.rs
+++ b/components/atoms/lib.rs
@@ -2,6 +2,4 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate string_cache;
-
 include!(concat!(env!("OUT_DIR"), "/atom.rs"));
diff --git a/components/bluetooth/lib.rs b/components/bluetooth/lib.rs
index 8d9f7bd0af5..e563c8fd8a4 100644
--- a/components/bluetooth/lib.rs
+++ b/components/bluetooth/lib.rs
@@ -4,15 +4,8 @@
 
 #[macro_use]
 extern crate bitflags;
-extern crate bluetooth_traits;
-extern crate device;
-extern crate embedder_traits;
-extern crate ipc_channel;
 #[macro_use]
 extern crate log;
-extern crate servo_config;
-extern crate servo_rand;
-extern crate uuid;
 
 pub mod test;
 
@@ -29,7 +22,7 @@ use embedder_traits::{EmbedderMsg, EmbedderProxy};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use servo_config::opts;
 use servo_config::prefs::PREFS;
-use servo_rand::Rng;
+use servo_rand::{self, Rng};
 use std::borrow::ToOwned;
 use std::collections::{HashMap, HashSet};
 use std::string::String;
diff --git a/components/bluetooth/test.rs b/components/bluetooth/test.rs
index 6138bbdb35e..0056f06767c 100644
--- a/components/bluetooth/test.rs
+++ b/components/bluetooth/test.rs
@@ -137,7 +137,7 @@ fn generate_id() -> Uuid {
 }
 
 // Set the adapter's name, is_powered and is_discoverable attributes
-fn set_adapter(adapter: &BluetoothAdapter, adapter_name: String) -> Result<(), Box<Error>> {
+fn set_adapter(adapter: &BluetoothAdapter, adapter_name: String) -> Result<(), Box<dyn Error>> {
     adapter.set_name(adapter_name)?;
     adapter.set_powered(true)?;
     adapter.set_discoverable(true)?;
@@ -149,7 +149,7 @@ fn create_device(
     adapter: &BluetoothAdapter,
     name: String,
     address: String,
-) -> Result<BluetoothDevice, Box<Error>> {
+) -> Result<BluetoothDevice, Box<dyn Error>> {
     let device = BluetoothDevice::create_mock_device(adapter.clone(), generate_id().to_string())?;
     device.set_name(Some(name))?;
     device.set_address(address)?;
@@ -163,7 +163,7 @@ fn create_device_with_uuids(
     name: String,
     address: String,
     uuids: Vec<String>,
-) -> Result<BluetoothDevice, Box<Error>> {
+) -> Result<BluetoothDevice, Box<dyn Error>> {
     let device = create_device(adapter, name, address)?;
     device.set_uuids(uuids)?;
     Ok(device)
@@ -173,7 +173,7 @@ fn create_device_with_uuids(
 fn create_service(
     device: &BluetoothDevice,
     uuid: String,
-) -> Result<BluetoothGATTService, Box<Error>> {
+) -> Result<BluetoothGATTService, Box<dyn Error>> {
     let service =
         BluetoothGATTService::create_mock_service(device.clone(), generate_id().to_string())?;
     service.set_uuid(uuid)?;
@@ -184,7 +184,7 @@ fn create_service(
 fn create_characteristic(
     service: &BluetoothGATTService,
     uuid: String,
-) -> Result<BluetoothGATTCharacteristic, Box<Error>> {
+) -> Result<BluetoothGATTCharacteristic, Box<dyn Error>> {
     let characteristic = BluetoothGATTCharacteristic::create_mock_characteristic(
         service.clone(),
         generate_id().to_string(),
@@ -198,7 +198,7 @@ fn create_characteristic_with_value(
     service: &BluetoothGATTService,
     uuid: String,
     value: Vec<u8>,
-) -> Result<BluetoothGATTCharacteristic, Box<Error>> {
+) -> Result<BluetoothGATTCharacteristic, Box<dyn Error>> {
     let characteristic = create_characteristic(service, uuid)?;
     characteristic.set_value(value)?;
     Ok(characteristic)
@@ -208,7 +208,7 @@ fn create_characteristic_with_value(
 fn create_descriptor(
     characteristic: &BluetoothGATTCharacteristic,
     uuid: String,
-) -> Result<BluetoothGATTDescriptor, Box<Error>> {
+) -> Result<BluetoothGATTDescriptor, Box<dyn Error>> {
     let descriptor = BluetoothGATTDescriptor::create_mock_descriptor(
         characteristic.clone(),
         generate_id().to_string(),
@@ -222,7 +222,7 @@ fn create_descriptor_with_value(
     characteristic: &BluetoothGATTCharacteristic,
     uuid: String,
     value: Vec<u8>,
-) -> Result<BluetoothGATTDescriptor, Box<Error>> {
+) -> Result<BluetoothGATTDescriptor, Box<dyn Error>> {
     let descriptor = create_descriptor(characteristic, uuid)?;
     descriptor.set_value(value)?;
     Ok(descriptor)
@@ -231,7 +231,7 @@ fn create_descriptor_with_value(
 fn create_heart_rate_service(
     device: &BluetoothDevice,
     empty: bool,
-) -> Result<BluetoothGATTService, Box<Error>> {
+) -> Result<BluetoothGATTService, Box<dyn Error>> {
     // Heart Rate Service
     let heart_rate_service = create_service(device, HEART_RATE_SERVICE_UUID.to_owned())?;
 
@@ -274,7 +274,7 @@ fn create_heart_rate_service(
 fn create_generic_access_service(
     device: &BluetoothDevice,
     empty: bool,
-) -> Result<BluetoothGATTService, Box<Error>> {
+) -> Result<BluetoothGATTService, Box<dyn Error>> {
     // Generic Access Service
     let generic_access_service = create_service(device, GENERIC_ACCESS_SERVICE_UUID.to_owned())?;
 
@@ -335,7 +335,7 @@ fn create_generic_access_service(
 fn create_heart_rate_device(
     adapter: &BluetoothAdapter,
     empty: bool,
-) -> Result<BluetoothDevice, Box<Error>> {
+) -> Result<BluetoothDevice, Box<dyn Error>> {
     // Heart Rate Device
     let heart_rate_device = create_device_with_uuids(
         adapter,
@@ -362,7 +362,7 @@ fn create_heart_rate_device(
 
 fn create_missing_characterisitc_heart_rate_device(
     adapter: &BluetoothAdapter,
-) -> Result<(), Box<Error>> {
+) -> Result<(), Box<dyn Error>> {
     let heart_rate_device_empty = create_heart_rate_device(adapter, true)?;
 
     let _generic_access_service_empty =
@@ -375,7 +375,7 @@ fn create_missing_characterisitc_heart_rate_device(
 
 fn create_missing_descriptor_heart_rate_device(
     adapter: &BluetoothAdapter,
-) -> Result<(), Box<Error>> {
+) -> Result<(), Box<dyn Error>> {
     let heart_rate_device_empty = create_heart_rate_device(adapter, true)?;
 
     let generic_access_service_empty =
@@ -399,7 +399,7 @@ fn create_missing_descriptor_heart_rate_device(
     Ok(())
 }
 
-fn create_two_heart_rate_services_device(adapter: &BluetoothAdapter) -> Result<(), Box<Error>> {
+fn create_two_heart_rate_services_device(adapter: &BluetoothAdapter) -> Result<(), Box<dyn Error>> {
     let heart_rate_device_empty = create_heart_rate_device(adapter, true)?;
 
     heart_rate_device_empty.set_uuids(vec![
@@ -435,7 +435,7 @@ fn create_two_heart_rate_services_device(adapter: &BluetoothAdapter) -> Result<(
     Ok(())
 }
 
-fn create_blocklisted_device(adapter: &BluetoothAdapter) -> Result<(), Box<Error>> {
+fn create_blocklisted_device(adapter: &BluetoothAdapter) -> Result<(), Box<dyn Error>> {
     let connectable_device = create_device_with_uuids(
         adapter,
         CONNECTABLE_DEVICE_NAME.to_owned(),
@@ -490,7 +490,7 @@ fn create_blocklisted_device(adapter: &BluetoothAdapter) -> Result<(), Box<Error
     Ok(())
 }
 
-fn create_glucose_heart_rate_devices(adapter: &BluetoothAdapter) -> Result<(), Box<Error>> {
+fn create_glucose_heart_rate_devices(adapter: &BluetoothAdapter) -> Result<(), Box<dyn Error>> {
     let glucose_devie = create_device_with_uuids(
         adapter,
         GLUCOSE_DEVICE_NAME.to_owned(),
@@ -517,7 +517,7 @@ fn create_glucose_heart_rate_devices(adapter: &BluetoothAdapter) -> Result<(), B
     Ok(())
 }
 
-pub fn test(manager: &mut BluetoothManager, data_set_name: String) -> Result<(), Box<Error>> {
+pub fn test(manager: &mut BluetoothManager, data_set_name: String) -> Result<(), Box<dyn Error>> {
     let may_existing_adapter = manager.get_or_create_adapter();
     let adapter = match may_existing_adapter.as_ref() {
         Some(adapter) => adapter,
diff --git a/components/bluetooth_traits/lib.rs b/components/bluetooth_traits/lib.rs
index bc77d885050..4733937d105 100644
--- a/components/bluetooth_traits/lib.rs
+++ b/components/bluetooth_traits/lib.rs
@@ -2,9 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate embedder_traits;
-extern crate ipc_channel;
-extern crate regex;
 #[macro_use]
 extern crate serde;
 
diff --git a/components/canvas/gl_context.rs b/components/canvas/gl_context.rs
index 077ea3b7f9f..9f8aeb2fe31 100644
--- a/components/canvas/gl_context.rs
+++ b/components/canvas/gl_context.rs
@@ -169,7 +169,7 @@ impl GLContextWrapper {
         }
     }
 
-    pub fn gl(&self) -> &gl::Gl {
+    pub fn gl(&self) -> &dyn gl::Gl {
         match *self {
             GLContextWrapper::Native(ref ctx) => ctx.gl(),
             GLContextWrapper::OSMesa(ref ctx) => ctx.gl(),
@@ -236,7 +236,7 @@ impl MainThreadDispatcher {
     }
 }
 impl GLContextDispatcher for MainThreadDispatcher {
-    fn dispatch(&self, f: Box<Fn() + Send>) {
+    fn dispatch(&self, f: Box<dyn Fn() + Send>) {
         self.compositor_proxy
             .lock()
             .unwrap()
diff --git a/components/canvas/lib.rs b/components/canvas/lib.rs
index 2e42b7e1902..ab785a5620c 100644
--- a/components/canvas/lib.rs
+++ b/components/canvas/lib.rs
@@ -4,23 +4,8 @@
 
 #![deny(unsafe_code)]
 
-extern crate azure;
-extern crate canvas_traits;
-extern crate compositing;
-extern crate cssparser;
-extern crate euclid;
-extern crate fnv;
-extern crate gleam;
-extern crate ipc_channel;
 #[macro_use]
 extern crate log;
-extern crate num_traits;
-extern crate offscreen_gl_context;
-extern crate pixels;
-extern crate serde_bytes;
-extern crate servo_config;
-extern crate webrender;
-extern crate webrender_api;
 
 pub mod canvas_data;
 pub mod canvas_paint_thread;
diff --git a/components/canvas/webgl_mode/inprocess.rs b/components/canvas/webgl_mode/inprocess.rs
index 1f7ade4eb56..bed3692268f 100644
--- a/components/canvas/webgl_mode/inprocess.rs
+++ b/components/canvas/webgl_mode/inprocess.rs
@@ -23,13 +23,13 @@ impl WebGLThreads {
     /// Creates a new WebGLThreads object
     pub fn new(
         gl_factory: GLContextFactory,
-        webrender_gl: Rc<gl::Gl>,
+        webrender_gl: Rc<dyn gl::Gl>,
         webrender_api_sender: webrender_api::RenderApiSender,
-        webvr_compositor: Option<Box<WebVRRenderHandler>>,
+        webvr_compositor: Option<Box<dyn WebVRRenderHandler>>,
     ) -> (
         WebGLThreads,
-        Box<webrender::ExternalImageHandler>,
-        Option<Box<webrender::OutputImageHandler>>,
+        Box<dyn webrender::ExternalImageHandler>,
+        Option<Box<dyn webrender::OutputImageHandler>>,
     ) {
         // This implementation creates a single `WebGLThread` for all the pipelines.
         let channel = WebGLThread::start(
@@ -70,7 +70,7 @@ impl WebGLThreads {
 
 /// Bridge between the webrender::ExternalImage callbacks and the WebGLThreads.
 struct WebGLExternalImages {
-    webrender_gl: Rc<gl::Gl>,
+    webrender_gl: Rc<dyn gl::Gl>,
     webgl_channel: WebGLSender<WebGLMsg>,
     // Used to avoid creating a new channel on each received WebRender request.
     lock_channel: (
@@ -80,7 +80,7 @@ struct WebGLExternalImages {
 }
 
 impl WebGLExternalImages {
-    fn new(webrender_gl: Rc<gl::Gl>, channel: WebGLSender<WebGLMsg>) -> Self {
+    fn new(webrender_gl: Rc<dyn gl::Gl>, channel: WebGLSender<WebGLMsg>) -> Self {
         Self {
             webrender_gl,
             webgl_channel: channel,
@@ -111,7 +111,7 @@ impl WebGLExternalImageApi for WebGLExternalImages {
 }
 
 /// Wrapper to send WebVR commands used in `WebGLThread`.
-struct WebVRRenderWrapper(Box<WebVRRenderHandler>);
+struct WebVRRenderWrapper(Box<dyn WebVRRenderHandler>);
 
 impl WebVRRenderHandler for WebVRRenderWrapper {
     fn handle(&mut self, command: WebVRCommand, texture: Option<(u32, Size2D<i32>)>) {
@@ -122,7 +122,7 @@ impl WebVRRenderHandler for WebVRRenderWrapper {
 /// struct used to implement DOMToTexture feature and webrender::OutputImageHandler trait.
 type OutputHandlerData = Option<(u32, Size2D<i32>)>;
 struct OutputHandler {
-    webrender_gl: Rc<gl::Gl>,
+    webrender_gl: Rc<dyn gl::Gl>,
     webgl_channel: WebGLSender<WebGLMsg>,
     // Used to avoid creating a new channel on each received WebRender request.
     lock_channel: (
@@ -133,7 +133,7 @@ struct OutputHandler {
 }
 
 impl OutputHandler {
-    fn new(webrender_gl: Rc<gl::Gl>, channel: WebGLSender<WebGLMsg>) -> Self {
+    fn new(webrender_gl: Rc<dyn gl::Gl>, channel: WebGLSender<WebGLMsg>) -> Self {
         Self {
             webrender_gl,
             webgl_channel: channel,
diff --git a/components/canvas/webgl_thread.rs b/components/canvas/webgl_thread.rs
index e47bfffdbcc..c40f4e1b169 100644
--- a/components/canvas/webgl_thread.rs
+++ b/components/canvas/webgl_thread.rs
@@ -1364,7 +1364,7 @@ impl WebGLImpl {
     }
 
     fn initialize_framebuffer(
-        gl: &gl::Gl,
+        gl: &dyn gl::Gl,
         state: &GLState,
         color: bool,
         depth: bool,
@@ -1424,7 +1424,7 @@ impl WebGLImpl {
     }
 
     #[allow(unsafe_code)]
-    fn link_program(gl: &gl::Gl, program: WebGLProgramId) -> ProgramLinkInfo {
+    fn link_program(gl: &dyn gl::Gl, program: WebGLProgramId) -> ProgramLinkInfo {
         gl.link_program(program.get());
         let mut linked = [0];
         unsafe {
@@ -1497,13 +1497,13 @@ impl WebGLImpl {
         }
     }
 
-    fn finish(gl: &gl::Gl, chan: &WebGLSender<()>) {
+    fn finish(gl: &dyn gl::Gl, chan: &WebGLSender<()>) {
         gl.finish();
         chan.send(()).unwrap();
     }
 
     fn shader_precision_format(
-        gl: &gl::Gl,
+        gl: &dyn gl::Gl,
         shader_type: u32,
         precision_type: u32,
         chan: &WebGLSender<(i32, i32, i32)>,
@@ -1512,13 +1512,13 @@ impl WebGLImpl {
         chan.send(result).unwrap();
     }
 
-    fn get_extensions(gl: &gl::Gl, chan: &WebGLSender<String>) {
+    fn get_extensions(gl: &dyn gl::Gl, chan: &WebGLSender<String>) {
         chan.send(gl.get_string(gl::EXTENSIONS)).unwrap();
     }
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.6
     fn get_framebuffer_attachment_parameter(
-        gl: &gl::Gl,
+        gl: &dyn gl::Gl,
         target: u32,
         attachment: u32,
         pname: u32,
@@ -1529,13 +1529,18 @@ impl WebGLImpl {
     }
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.7
-    fn get_renderbuffer_parameter(gl: &gl::Gl, target: u32, pname: u32, chan: &WebGLSender<i32>) {
+    fn get_renderbuffer_parameter(
+        gl: &dyn gl::Gl,
+        target: u32,
+        pname: u32,
+        chan: &WebGLSender<i32>,
+    ) {
         let parameter = gl.get_renderbuffer_parameter_iv(target, pname);
         chan.send(parameter).unwrap();
     }
 
     fn uniform_location(
-        gl: &gl::Gl,
+        gl: &dyn gl::Gl,
         program_id: WebGLProgramId,
         name: &str,
         chan: &WebGLSender<i32>,
@@ -1545,18 +1550,18 @@ impl WebGLImpl {
         chan.send(location).unwrap();
     }
 
-    fn shader_info_log(gl: &gl::Gl, shader_id: WebGLShaderId, chan: &WebGLSender<String>) {
+    fn shader_info_log(gl: &dyn gl::Gl, shader_id: WebGLShaderId, chan: &WebGLSender<String>) {
         let log = gl.get_shader_info_log(shader_id.get());
         chan.send(log).unwrap();
     }
 
-    fn program_info_log(gl: &gl::Gl, program_id: WebGLProgramId, chan: &WebGLSender<String>) {
+    fn program_info_log(gl: &dyn gl::Gl, program_id: WebGLProgramId, chan: &WebGLSender<String>) {
         let log = gl.get_program_info_log(program_id.get());
         chan.send(log).unwrap();
     }
 
     #[allow(unsafe_code)]
-    fn create_buffer(gl: &gl::Gl, chan: &WebGLSender<Option<WebGLBufferId>>) {
+    fn create_buffer(gl: &dyn gl::Gl, chan: &WebGLSender<Option<WebGLBufferId>>) {
         let buffer = gl.gen_buffers(1)[0];
         let buffer = if buffer == 0 {
             None
@@ -1567,7 +1572,7 @@ impl WebGLImpl {
     }
 
     #[allow(unsafe_code)]
-    fn create_framebuffer(gl: &gl::Gl, chan: &WebGLSender<Option<WebGLFramebufferId>>) {
+    fn create_framebuffer(gl: &dyn gl::Gl, chan: &WebGLSender<Option<WebGLFramebufferId>>) {
         let framebuffer = gl.gen_framebuffers(1)[0];
         let framebuffer = if framebuffer == 0 {
             None
@@ -1578,7 +1583,7 @@ impl WebGLImpl {
     }
 
     #[allow(unsafe_code)]
-    fn create_renderbuffer(gl: &gl::Gl, chan: &WebGLSender<Option<WebGLRenderbufferId>>) {
+    fn create_renderbuffer(gl: &dyn gl::Gl, chan: &WebGLSender<Option<WebGLRenderbufferId>>) {
         let renderbuffer = gl.gen_renderbuffers(1)[0];
         let renderbuffer = if renderbuffer == 0 {
             None
@@ -1589,7 +1594,7 @@ impl WebGLImpl {
     }
 
     #[allow(unsafe_code)]
-    fn create_texture(gl: &gl::Gl, chan: &WebGLSender<Option<WebGLTextureId>>) {
+    fn create_texture(gl: &dyn gl::Gl, chan: &WebGLSender<Option<WebGLTextureId>>) {
         let texture = gl.gen_textures(1)[0];
         let texture = if texture == 0 {
             None
@@ -1600,7 +1605,7 @@ impl WebGLImpl {
     }
 
     #[allow(unsafe_code)]
-    fn create_program(gl: &gl::Gl, chan: &WebGLSender<Option<WebGLProgramId>>) {
+    fn create_program(gl: &dyn gl::Gl, chan: &WebGLSender<Option<WebGLProgramId>>) {
         let program = gl.create_program();
         let program = if program == 0 {
             None
@@ -1611,7 +1616,7 @@ impl WebGLImpl {
     }
 
     #[allow(unsafe_code)]
-    fn create_shader(gl: &gl::Gl, shader_type: u32, chan: &WebGLSender<Option<WebGLShaderId>>) {
+    fn create_shader(gl: &dyn gl::Gl, shader_type: u32, chan: &WebGLSender<Option<WebGLShaderId>>) {
         let shader = gl.create_shader(shader_type);
         let shader = if shader == 0 {
             None
@@ -1622,7 +1627,7 @@ impl WebGLImpl {
     }
 
     #[allow(unsafe_code)]
-    fn create_vertex_array(gl: &gl::Gl, chan: &WebGLSender<Option<WebGLVertexArrayId>>) {
+    fn create_vertex_array(gl: &dyn gl::Gl, chan: &WebGLSender<Option<WebGLVertexArrayId>>) {
         let vao = gl.gen_vertex_arrays(1)[0];
         let vao = if vao == 0 {
             None
@@ -1634,7 +1639,7 @@ impl WebGLImpl {
 
     #[inline]
     fn bind_framebuffer<Native: NativeGLContextMethods>(
-        gl: &gl::Gl,
+        gl: &dyn gl::Gl,
         target: u32,
         request: WebGLFramebufferBindingRequest,
         ctx: &GLContext<Native>,
@@ -1650,7 +1655,7 @@ impl WebGLImpl {
     }
 
     #[inline]
-    fn compile_shader(gl: &gl::Gl, shader_id: WebGLShaderId, source: &str) {
+    fn compile_shader(gl: &dyn gl::Gl, shader_id: WebGLShaderId, source: &str) {
         gl.shader_source(shader_id.get(), &[source.as_bytes()]);
         gl.compile_shader(shader_id.get());
     }
diff --git a/components/canvas_traits/lib.rs b/components/canvas_traits/lib.rs
index 2c386b944ef..2e11d1704c6 100644
--- a/components/canvas_traits/lib.rs
+++ b/components/canvas_traits/lib.rs
@@ -6,21 +6,12 @@
 #![crate_type = "rlib"]
 #![deny(unsafe_code)]
 
-extern crate cssparser;
-extern crate euclid;
-extern crate gleam;
-extern crate ipc_channel;
 #[macro_use]
 extern crate lazy_static;
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate offscreen_gl_context;
 #[macro_use]
 extern crate serde;
-extern crate serde_bytes;
-extern crate servo_config;
-extern crate webrender_api;
 
 pub mod canvas;
 pub mod webgl;
diff --git a/components/channel/lib.rs b/components/channel/lib.rs
index fd8dc7e5824..3e286ef7f98 100644
--- a/components/channel/lib.rs
+++ b/components/channel/lib.rs
@@ -2,16 +2,13 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate crossbeam_channel;
-extern crate ipc_channel;
-extern crate serde;
-
 pub mod base_channel {
     pub use crossbeam_channel::*;
 }
 // Needed to re-export the select macro.
 pub use crossbeam_channel::*;
 
+use crossbeam_channel;
 use ipc_channel::ipc::IpcReceiver;
 use ipc_channel::router::ROUTER;
 use serde::{Deserialize, Serialize};
diff --git a/components/compositing/build.rs b/components/compositing/build.rs
index 54532276222..c9b97801f51 100644
--- a/components/compositing/build.rs
+++ b/components/compositing/build.rs
@@ -2,12 +2,11 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate toml;
-
 use std::env;
 use std::fs::File;
 use std::io::{Read, Write};
 use std::path::Path;
+use toml;
 
 fn main() {
     let lockfile_path = Path::new(&env::var("CARGO_MANIFEST_DIR").unwrap())
diff --git a/components/compositing/compositor.rs b/components/compositing/compositor.rs
index c3974c7fd01..f357f6522ee 100644
--- a/components/compositing/compositor.rs
+++ b/components/compositing/compositor.rs
@@ -263,7 +263,7 @@ impl RenderNotifier {
 }
 
 impl webrender_api::RenderNotifier for RenderNotifier {
-    fn clone(&self) -> Box<webrender_api::RenderNotifier> {
+    fn clone(&self) -> Box<dyn webrender_api::RenderNotifier> {
         Box::new(RenderNotifier::new(self.compositor_proxy.clone()))
     }
 
diff --git a/components/compositing/compositor_thread.rs b/components/compositing/compositor_thread.rs
index a897f141fed..a4859d58f79 100644
--- a/components/compositing/compositor_thread.rs
+++ b/components/compositing/compositor_thread.rs
@@ -23,7 +23,7 @@ use webrender_api::{self, DeviceIntPoint, DeviceUintSize};
 /// Sends messages to the compositor.
 pub struct CompositorProxy {
     pub sender: Sender<Msg>,
-    pub event_loop_waker: Box<EventLoopWaker>,
+    pub event_loop_waker: Box<dyn EventLoopWaker>,
 }
 
 impl CompositorProxy {
@@ -98,7 +98,7 @@ pub enum Msg {
     /// Runs a closure in the compositor thread.
     /// It's used to dispatch functions from webrender to the main thread's event loop.
     /// Required to allow WGL GLContext sharing in Windows.
-    Dispatch(Box<Fn() + Send>),
+    Dispatch(Box<dyn Fn() + Send>),
     /// Indicates to the compositor that it needs to record the time when the frame with
     /// the given ID (epoch) is painted and report it to the layout thread of the given
     /// pipeline ID.
diff --git a/components/compositing/gl.rs b/components/compositing/gl.rs
index 6637ef203ea..59c1225cd91 100644
--- a/components/compositing/gl.rs
+++ b/components/compositing/gl.rs
@@ -14,7 +14,7 @@ pub struct RenderTargetInfo {
 }
 
 pub fn initialize_png(
-    gl: &gl::Gl,
+    gl: &dyn gl::Gl,
     width: DeviceUintLength,
     height: DeviceUintLength,
 ) -> RenderTargetInfo {
@@ -80,7 +80,7 @@ pub fn initialize_png(
 }
 
 pub fn draw_img(
-    gl: &gl::Gl,
+    gl: &dyn gl::Gl,
     render_target_info: RenderTargetInfo,
     width: DeviceUintLength,
     height: DeviceUintLength,
diff --git a/components/compositing/lib.rs b/components/compositing/lib.rs
index c631f39275e..d54feac56bb 100644
--- a/components/compositing/lib.rs
+++ b/components/compositing/lib.rs
@@ -4,30 +4,8 @@
 
 #![deny(unsafe_code)]
 
-extern crate embedder_traits;
-extern crate euclid;
-extern crate gfx_traits;
-#[cfg(feature = "gleam")]
-extern crate gleam;
-#[cfg(feature = "gleam")]
-extern crate image;
-extern crate ipc_channel;
-extern crate keyboard_types;
-extern crate libc;
 #[macro_use]
 extern crate log;
-extern crate msg;
-extern crate net_traits;
-extern crate profile_traits;
-extern crate script_traits;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_geometry;
-extern crate servo_url;
-extern crate style_traits;
-extern crate time;
-extern crate webrender;
-extern crate webrender_api;
 
 pub use crate::compositor::IOCompositor;
 pub use crate::compositor::RenderNotifier;
diff --git a/components/compositing/windowing.rs b/components/compositing/windowing.rs
index 9ff7e919746..087062c3fc2 100644
--- a/components/compositing/windowing.rs
+++ b/components/compositing/windowing.rs
@@ -132,9 +132,9 @@ pub trait WindowMethods {
     fn prepare_for_composite(&self) -> bool;
     /// Return the GL function pointer trait.
     #[cfg(feature = "gleam")]
-    fn gl(&self) -> Rc<gl::Gl>;
+    fn gl(&self) -> Rc<dyn gl::Gl>;
     /// Returns a thread-safe object to wake up the window's event loop.
-    fn create_event_loop_waker(&self) -> Box<EventLoopWaker>;
+    fn create_event_loop_waker(&self) -> Box<dyn EventLoopWaker>;
     /// Get the coordinates of the native window, the screen and the framebuffer.
     fn get_coordinates(&self) -> EmbedderCoordinates;
     /// Set whether the application is currently animating.
diff --git a/components/config/lib.rs b/components/config/lib.rs
index 7f24eeb7c5c..d7baff3a71d 100644
--- a/components/config/lib.rs
+++ b/components/config/lib.rs
@@ -4,22 +4,12 @@
 
 #![deny(unsafe_code)]
 
-#[cfg(not(target_os = "android"))]
-extern crate dirs;
-extern crate embedder_traits;
-extern crate euclid;
-extern crate getopts;
 #[macro_use]
 extern crate lazy_static;
 #[macro_use]
 extern crate log;
-extern crate num_cpus;
 #[macro_use]
 extern crate serde;
-extern crate serde_json;
-extern crate servo_geometry;
-extern crate servo_url;
-extern crate url;
 
 pub mod basedir;
 #[allow(unsafe_code)]
diff --git a/components/config/tests/opts.rs b/components/config/tests/opts.rs
index 3e427074823..030f398a7cb 100644
--- a/components/config/tests/opts.rs
+++ b/components/config/tests/opts.rs
@@ -2,8 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate servo_config;
-
 use servo_config::opts::{parse_pref_from_command_line, parse_url_or_filename};
 use servo_config::prefs::{PrefValue, PREFS};
 use std::path::Path;
diff --git a/components/config/tests/prefs.rs b/components/config/tests/prefs.rs
index ee3916b7f5a..e4ff276ebb5 100644
--- a/components/config/tests/prefs.rs
+++ b/components/config/tests/prefs.rs
@@ -2,8 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate servo_config;
-
 use servo_config::basedir;
 use servo_config::prefs::{read_prefs, PrefValue, PREFS};
 use std::fs::{self, File};
diff --git a/components/constellation/lib.rs b/components/constellation/lib.rs
index 54235a9b09c..1b4befa3af6 100644
--- a/components/constellation/lib.rs
+++ b/components/constellation/lib.rs
@@ -5,43 +5,10 @@
 #![deny(unsafe_code)]
 #![cfg_attr(feature = "unstable", feature(conservative_impl_trait))]
 
-extern crate backtrace;
-extern crate bluetooth_traits;
-extern crate canvas;
-extern crate canvas_traits;
-extern crate clipboard;
-extern crate compositing;
-extern crate debugger;
-extern crate devtools_traits;
-#[cfg(not(target_os = "ios"))]
-extern crate embedder_traits;
-extern crate euclid;
-#[cfg(all(not(target_os = "windows"), not(target_os = "ios")))]
-extern crate gaol;
-extern crate gfx;
-extern crate gfx_traits;
-extern crate http;
-extern crate ipc_channel;
-extern crate keyboard_types;
-extern crate layout_traits;
 #[macro_use]
 extern crate log;
-extern crate metrics;
-extern crate msg;
-extern crate net;
-extern crate net_traits;
-extern crate profile_traits;
-extern crate script_traits;
-extern crate serde;
 #[macro_use]
 extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_rand;
-extern crate servo_remutex;
-extern crate servo_url;
-extern crate style_traits;
-extern crate webrender_api;
-extern crate webvr_traits;
 
 mod browsingcontext;
 mod constellation;
diff --git a/components/debugger/lib.rs b/components/debugger/lib.rs
index c6ba6147826..a609bd6129f 100644
--- a/components/debugger/lib.rs
+++ b/components/debugger/lib.rs
@@ -4,11 +4,10 @@
 
 #[macro_use]
 extern crate log;
-extern crate servo_channel;
-extern crate ws;
 
+use servo_channel;
 use std::thread;
-use ws::{Builder, CloseCode, Handler, Handshake};
+use ws::{self, Builder, CloseCode, Handler, Handshake};
 
 enum Message {
     ShutdownServer,
diff --git a/components/deny_public_fields/lib.rs b/components/deny_public_fields/lib.rs
index 28fbf85add0..e64ac990081 100644
--- a/components/deny_public_fields/lib.rs
+++ b/components/deny_public_fields/lib.rs
@@ -3,11 +3,10 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 extern crate proc_macro;
-extern crate syn;
-#[macro_use]
-extern crate synstructure;
 
 use std::str::FromStr;
+use syn;
+use synstructure::{self, decl_derive};
 
 decl_derive!([DenyPublicFields] => deny_public_fields_derive);
 
diff --git a/components/devtools/actor.rs b/components/devtools/actor.rs
index 634622a2068..73180a784ed 100644
--- a/components/devtools/actor.rs
+++ b/components/devtools/actor.rs
@@ -33,23 +33,23 @@ pub trait Actor: Any + ActorAsAny {
 }
 
 pub trait ActorAsAny {
-    fn actor_as_any(&self) -> &Any;
-    fn actor_as_any_mut(&mut self) -> &mut Any;
+    fn actor_as_any(&self) -> &dyn Any;
+    fn actor_as_any_mut(&mut self) -> &mut dyn Any;
 }
 
 impl<T: Actor> ActorAsAny for T {
-    fn actor_as_any(&self) -> &Any {
+    fn actor_as_any(&self) -> &dyn Any {
         self
     }
-    fn actor_as_any_mut(&mut self) -> &mut Any {
+    fn actor_as_any_mut(&mut self) -> &mut dyn Any {
         self
     }
 }
 
 /// A list of known, owned actors.
 pub struct ActorRegistry {
-    actors: HashMap<String, Box<Actor + Send>>,
-    new_actors: RefCell<Vec<Box<Actor + Send>>>,
+    actors: HashMap<String, Box<dyn Actor + Send>>,
+    new_actors: RefCell<Vec<Box<dyn Actor + Send>>>,
     old_actors: RefCell<Vec<String>>,
     script_actors: RefCell<HashMap<String, String>>,
     shareable: Option<Arc<Mutex<ActorRegistry>>>,
@@ -131,11 +131,11 @@ impl ActorRegistry {
     }
 
     /// Add an actor to the registry of known actors that can receive messages.
-    pub fn register(&mut self, actor: Box<Actor + Send>) {
+    pub fn register(&mut self, actor: Box<dyn Actor + Send>) {
         self.actors.insert(actor.name(), actor);
     }
 
-    pub fn register_later(&self, actor: Box<Actor + Send>) {
+    pub fn register_later(&self, actor: Box<dyn Actor + Send>) {
         let mut actors = self.new_actors.borrow_mut();
         actors.push(actor);
     }
diff --git a/components/devtools/lib.rs b/components/devtools/lib.rs
index be40e70eec6..0768a79ed09 100644
--- a/components/devtools/lib.rs
+++ b/components/devtools/lib.rs
@@ -12,20 +12,10 @@
 #![allow(non_snake_case)]
 #![deny(unsafe_code)]
 
-extern crate devtools_traits;
-extern crate headers_core;
-extern crate headers_ext;
-extern crate http;
-extern crate hyper;
-extern crate ipc_channel;
 #[macro_use]
 extern crate log;
-extern crate msg;
 #[macro_use]
 extern crate serde;
-extern crate serde_json;
-extern crate servo_channel;
-extern crate time;
 
 use crate::actor::{Actor, ActorRegistry};
 use crate::actors::browsing_context::BrowsingContextActor;
diff --git a/components/devtools_traits/lib.rs b/components/devtools_traits/lib.rs
index dc0979f580c..e0280345169 100644
--- a/components/devtools_traits/lib.rs
+++ b/components/devtools_traits/lib.rs
@@ -13,16 +13,10 @@
 
 #[macro_use]
 extern crate bitflags;
-extern crate http;
-extern crate ipc_channel;
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate msg;
 #[macro_use]
 extern crate serde;
-extern crate servo_url;
-extern crate time;
 
 use http::method::Method;
 use http::HeaderMap;
@@ -30,8 +24,7 @@ use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::PipelineId;
 use servo_url::ServoUrl;
 use std::net::TcpStream;
-use time::Duration;
-use time::Tm;
+use time::{self, Duration, Tm};
 
 // Information would be attached to NewGlobal to be received and show in devtools.
 // Extend these fields if we need more information.
diff --git a/components/dom_struct/lib.rs b/components/dom_struct/lib.rs
index bd3a9765e29..95d7b0446d5 100644
--- a/components/dom_struct/lib.rs
+++ b/components/dom_struct/lib.rs
@@ -3,7 +3,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 extern crate proc_macro;
-
 #[macro_use]
 extern crate quote;
 extern crate syn;
diff --git a/components/embedder_traits/lib.rs b/components/embedder_traits/lib.rs
index 48c231ca3cd..96364c5e639 100644
--- a/components/embedder_traits/lib.rs
+++ b/components/embedder_traits/lib.rs
@@ -2,19 +2,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate ipc_channel;
-extern crate keyboard_types;
 #[macro_use]
 extern crate lazy_static;
 #[macro_use]
 extern crate log;
-extern crate msg;
 #[macro_use]
 extern crate serde;
-extern crate servo_channel;
-extern crate servo_url;
-extern crate style_traits;
-extern crate webrender_api;
 
 pub mod resources;
 
diff --git a/components/geometry/lib.rs b/components/geometry/lib.rs
index 2f421f6a277..654bf8b3c80 100644
--- a/components/geometry/lib.rs
+++ b/components/geometry/lib.rs
@@ -2,13 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate app_units;
-extern crate euclid;
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate style_traits;
-extern crate webrender_api;
 
 use app_units::{Au, MAX_AU, MIN_AU};
 use euclid::{Length, Point2D, Rect, Size2D};
diff --git a/components/gfx/lib.rs b/components/gfx/lib.rs
index 442a9c8ae3a..24dbcde26cb 100644
--- a/components/gfx/lib.rs
+++ b/components/gfx/lib.rs
@@ -4,75 +4,16 @@
 
 #![deny(unsafe_code)]
 
-extern crate app_units;
 #[macro_use]
 extern crate bitflags;
-
-// Mac OS-specific library dependencies
-#[cfg(target_os = "macos")]
-extern crate byteorder;
-#[cfg(target_os = "macos")]
-extern crate core_foundation;
-#[cfg(target_os = "macos")]
-extern crate core_graphics;
-#[cfg(target_os = "macos")]
-extern crate core_text;
-
-// Windows-specific library dependencies
-#[cfg(target_os = "windows")]
-extern crate dwrote;
-
-extern crate euclid;
-extern crate fnv;
-
-#[cfg(target_os = "linux")]
-extern crate fontconfig;
-extern crate fontsan;
-#[cfg(any(target_os = "linux", target_os = "android"))]
-extern crate freetype;
-extern crate gfx_traits;
-
-// Eventually we would like the shaper to be pluggable, as many operating systems have their own
-// shapers. For now, however, this is a hard dependency.
-extern crate harfbuzz_sys as harfbuzz;
-
-extern crate ipc_channel;
 #[macro_use]
 extern crate lazy_static;
-#[cfg(any(target_os = "linux", target_os = "android"))]
-extern crate libc;
 #[macro_use]
 extern crate log;
-#[cfg_attr(target_os = "windows", macro_use)]
-extern crate malloc_size_of;
-extern crate net_traits;
-extern crate ordered_float;
-#[cfg(all(
-    feature = "unstable",
-    any(target_feature = "sse2", target_feature = "neon")
-))]
-extern crate packed_simd;
-extern crate range;
 #[macro_use]
 extern crate serde;
-#[cfg(any(target_os = "linux", target_os = "android"))]
-extern crate servo_allocator;
-extern crate servo_arc;
 #[macro_use]
 extern crate servo_atoms;
-extern crate servo_url;
-extern crate smallvec;
-extern crate style;
-extern crate time;
-#[cfg(target_os = "windows")]
-extern crate truetype;
-extern crate ucd;
-extern crate unicode_bidi;
-extern crate unicode_script;
-extern crate webrender_api;
-extern crate xi_unicode;
-#[cfg(target_os = "android")]
-extern crate xml5ever;
 
 // Fonts
 #[macro_use]
diff --git a/components/gfx/platform/windows/font_context.rs b/components/gfx/platform/windows/font_context.rs
index 7d304ed138d..400988d032f 100644
--- a/components/gfx/platform/windows/font_context.rs
+++ b/components/gfx/platform/windows/font_context.rs
@@ -2,6 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use malloc_size_of::malloc_size_of_is_0;
+
 #[derive(Clone, Debug)]
 pub struct FontContextHandle;
 
diff --git a/components/gfx/tests/font_context.rs b/components/gfx/tests/font_context.rs
index d4dea69597d..6be4cbe263b 100644
--- a/components/gfx/tests/font_context.rs
+++ b/components/gfx/tests/font_context.rs
@@ -2,13 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate app_units;
-extern crate gfx;
-extern crate servo_arc;
-extern crate servo_atoms;
-extern crate style;
-extern crate webrender_api;
-
 use app_units::Au;
 use gfx::font::{
     fallback_font_families, FontDescriptor, FontFamilyDescriptor, FontFamilyName, FontSearchScope,
@@ -31,6 +24,7 @@ use style::values::computed::font::{
 };
 use style::values::computed::font::{FontStretch, FontWeight, SingleFontFamily};
 use style::values::generics::font::FontStyle;
+use webrender_api;
 
 struct TestFontSource {
     handle: FontContextHandle,
diff --git a/components/gfx/tests/font_template.rs b/components/gfx/tests/font_template.rs
index 8d1935f738d..132e067cf1a 100644
--- a/components/gfx/tests/font_template.rs
+++ b/components/gfx/tests/font_template.rs
@@ -2,13 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#[cfg(not(target_os = "macos"))]
-extern crate gfx;
-#[cfg(not(target_os = "macos"))]
-extern crate servo_atoms;
-#[cfg(not(target_os = "macos"))]
-extern crate style;
-
 // Test doesn't yet run on Mac, see https://github.com/servo/servo/pull/19928 for explanation.
 #[cfg(not(target_os = "macos"))]
 #[test]
diff --git a/components/gfx/tests/text_util.rs b/components/gfx/tests/text_util.rs
index c35a06a2e2f..297823041d8 100644
--- a/components/gfx/tests/text_util.rs
+++ b/components/gfx/tests/text_util.rs
@@ -2,8 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate gfx;
-
 use gfx::text::util::{transform_text, CompressionMode};
 
 #[test]
diff --git a/components/gfx/text/shaping/harfbuzz.rs b/components/gfx/text/shaping/harfbuzz.rs
index 675c57b4615..ecd575d9b91 100644
--- a/components/gfx/text/shaping/harfbuzz.rs
+++ b/components/gfx/text/shaping/harfbuzz.rs
@@ -6,37 +6,39 @@
 
 use app_units::Au;
 use crate::font::{Font, FontTableMethods, FontTableTag, ShapingFlags, ShapingOptions, KERN};
-use crate::harfbuzz::hb_blob_t;
-use crate::harfbuzz::hb_bool_t;
-use crate::harfbuzz::hb_buffer_add_utf8;
-use crate::harfbuzz::hb_buffer_destroy;
-use crate::harfbuzz::hb_buffer_get_glyph_positions;
-use crate::harfbuzz::hb_buffer_get_length;
-use crate::harfbuzz::hb_face_destroy;
-use crate::harfbuzz::hb_feature_t;
-use crate::harfbuzz::hb_font_create;
-use crate::harfbuzz::hb_font_funcs_create;
-use crate::harfbuzz::hb_font_funcs_set_glyph_h_advance_func;
-use crate::harfbuzz::hb_font_funcs_set_glyph_h_kerning_func;
-use crate::harfbuzz::hb_font_funcs_set_nominal_glyph_func;
-use crate::harfbuzz::hb_font_set_funcs;
-use crate::harfbuzz::hb_font_set_ppem;
-use crate::harfbuzz::hb_font_set_scale;
-use crate::harfbuzz::hb_glyph_info_t;
-use crate::harfbuzz::hb_glyph_position_t;
-use crate::harfbuzz::{hb_blob_create, hb_face_create_for_tables};
-use crate::harfbuzz::{hb_buffer_create, hb_font_destroy};
-use crate::harfbuzz::{hb_buffer_get_glyph_infos, hb_shape};
-use crate::harfbuzz::{hb_buffer_set_direction, hb_buffer_set_script};
-use crate::harfbuzz::{hb_buffer_t, hb_codepoint_t, hb_font_funcs_t};
-use crate::harfbuzz::{hb_face_t, hb_font_t};
-use crate::harfbuzz::{hb_position_t, hb_tag_t};
-use crate::harfbuzz::{HB_DIRECTION_LTR, HB_DIRECTION_RTL, HB_MEMORY_MODE_READONLY};
 use crate::platform::font::FontTable;
 use crate::text::glyph::{ByteIndex, GlyphData, GlyphId, GlyphStore};
 use crate::text::shaping::ShaperMethods;
 use crate::text::util::{fixed_to_float, float_to_fixed, is_bidi_control};
 use euclid::Point2D;
+// Eventually we would like the shaper to be pluggable, as many operating systems have their own
+// shapers. For now, however, HarfBuzz is a hard dependency.
+use harfbuzz_sys::hb_blob_t;
+use harfbuzz_sys::hb_bool_t;
+use harfbuzz_sys::hb_buffer_add_utf8;
+use harfbuzz_sys::hb_buffer_destroy;
+use harfbuzz_sys::hb_buffer_get_glyph_positions;
+use harfbuzz_sys::hb_buffer_get_length;
+use harfbuzz_sys::hb_face_destroy;
+use harfbuzz_sys::hb_feature_t;
+use harfbuzz_sys::hb_font_create;
+use harfbuzz_sys::hb_font_funcs_create;
+use harfbuzz_sys::hb_font_funcs_set_glyph_h_advance_func;
+use harfbuzz_sys::hb_font_funcs_set_glyph_h_kerning_func;
+use harfbuzz_sys::hb_font_funcs_set_nominal_glyph_func;
+use harfbuzz_sys::hb_font_set_funcs;
+use harfbuzz_sys::hb_font_set_ppem;
+use harfbuzz_sys::hb_font_set_scale;
+use harfbuzz_sys::hb_glyph_info_t;
+use harfbuzz_sys::hb_glyph_position_t;
+use harfbuzz_sys::{hb_blob_create, hb_face_create_for_tables};
+use harfbuzz_sys::{hb_buffer_create, hb_font_destroy};
+use harfbuzz_sys::{hb_buffer_get_glyph_infos, hb_shape};
+use harfbuzz_sys::{hb_buffer_set_direction, hb_buffer_set_script};
+use harfbuzz_sys::{hb_buffer_t, hb_codepoint_t, hb_font_funcs_t};
+use harfbuzz_sys::{hb_face_t, hb_font_t};
+use harfbuzz_sys::{hb_position_t, hb_tag_t};
+use harfbuzz_sys::{HB_DIRECTION_LTR, HB_DIRECTION_RTL, HB_MEMORY_MODE_READONLY};
 use std::os::raw::{c_char, c_int, c_uint, c_void};
 use std::{char, cmp, ptr};
 
diff --git a/components/gfx/text/shaping/mod.rs b/components/gfx/text/shaping/mod.rs
index 8c59c13427a..9f78c0d75ac 100644
--- a/components/gfx/text/shaping/mod.rs
+++ b/components/gfx/text/shaping/mod.rs
@@ -10,7 +10,7 @@
 use crate::font::ShapingOptions;
 use crate::text::glyph::GlyphStore;
 
-pub use crate::text::shaping::harfbuzz::Shaper;
+pub use self::harfbuzz::Shaper;
 
 pub mod harfbuzz;
 
diff --git a/components/gfx_traits/lib.rs b/components/gfx_traits/lib.rs
index 308c01cd279..f540ed61be6 100644
--- a/components/gfx_traits/lib.rs
+++ b/components/gfx_traits/lib.rs
@@ -6,7 +6,6 @@
 #![crate_type = "rlib"]
 #![deny(unsafe_code)]
 
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
 #[macro_use]
diff --git a/components/jstraceable_derive/lib.rs b/components/jstraceable_derive/lib.rs
index 571a50b7a1e..f00992b80dc 100644
--- a/components/jstraceable_derive/lib.rs
+++ b/components/jstraceable_derive/lib.rs
@@ -2,12 +2,13 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate quote;
 #[macro_use]
 extern crate syn;
 #[macro_use]
 extern crate synstructure;
 
+use quote;
+
 decl_derive!([JSTraceable] => js_traceable_derive);
 
 fn js_traceable_derive(s: synstructure::Structure) -> quote::Tokens {
diff --git a/components/layout/animation.rs b/components/layout/animation.rs
index 2a2b49d9715..0903c1b7fa5 100644
--- a/components/layout/animation.rs
+++ b/components/layout/animation.rs
@@ -163,7 +163,7 @@ pub fn update_animation_state<E>(
 /// lock held.
 pub fn recalc_style_for_animations<E>(
     context: &LayoutContext,
-    flow: &mut Flow,
+    flow: &mut dyn Flow,
     animations: &FxHashMap<OpaqueNode, Vec<Animation>>,
 ) where
     E: TElement,
diff --git a/components/layout/block.rs b/components/layout/block.rs
index 9fbd7434ea9..429662d29b5 100644
--- a/components/layout/block.rs
+++ b/components/layout/block.rs
@@ -546,7 +546,7 @@ pub struct AbsoluteAssignBSizesTraversal<'a>(pub &'a SharedStyleContext<'a>);
 
 impl<'a> PreorderFlowTraversal for AbsoluteAssignBSizesTraversal<'a> {
     #[inline]
-    fn process(&self, flow: &mut Flow) {
+    fn process(&self, flow: &mut dyn Flow) {
         if !flow.is_block_like() {
             return;
         }
@@ -938,7 +938,7 @@ impl BlockFlow {
         layout_context: &LayoutContext,
         mut fragmentation_context: Option<FragmentationContext>,
         margins_may_collapse: MarginsMayCollapseFlag,
-    ) -> Option<Arc<Flow>> {
+    ) -> Option<Arc<dyn Flow>> {
         let _scope = layout_debug_scope!("assign_block_size_block_base {:x}", self.base.debug_id());
 
         let mut break_at = None;
@@ -1272,7 +1272,7 @@ impl BlockFlow {
             }
         }
 
-        if (&*self as &Flow).contains_roots_of_absolute_flow_tree() {
+        if (&*self as &dyn Flow).contains_roots_of_absolute_flow_tree() {
             // Assign block-sizes for all flows in this absolute flow tree.
             // This is preorder because the block-size of an absolute flow may depend on
             // the block-size of its containing block, which may also be an absolute flow.
@@ -1307,7 +1307,7 @@ impl BlockFlow {
                 if let Some(child) = child_remaining {
                     children.push_front_arc(child);
                 }
-                Some(Arc::new(self.clone_with_children(children)) as Arc<Flow>)
+                Some(Arc::new(self.clone_with_children(children)) as Arc<dyn Flow>)
             }
         })
     }
@@ -1592,7 +1592,7 @@ impl BlockFlow {
         content_inline_size: Au,
         mut callback: F,
     ) where
-        F: FnMut(&mut Flow, usize, Au, WritingMode, &mut Au, &mut Au),
+        F: FnMut(&mut dyn Flow, usize, Au, WritingMode, &mut Au, &mut Au),
     {
         let flags = self.base.flags.clone();
 
@@ -2246,7 +2246,7 @@ impl Flow for BlockFlow {
             self.assign_inline_position_for_formatting_context(layout_context, content_box);
         }
 
-        if (self as &Flow).floats_might_flow_through() {
+        if (self as &dyn Flow).floats_might_flow_through() {
             self.base.thread_id = parent_thread_id;
             if self
                 .base
@@ -2283,7 +2283,7 @@ impl Flow for BlockFlow {
         &mut self,
         layout_context: &LayoutContext,
         fragmentation_context: Option<FragmentationContext>,
-    ) -> Option<Arc<Flow>> {
+    ) -> Option<Arc<dyn Flow>> {
         if self.fragment.is_replaced() {
             let _scope = layout_debug_scope!(
                 "assign_replaced_block_size_if_necessary {:x}",
@@ -2613,7 +2613,7 @@ impl Flow for BlockFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -2641,7 +2641,7 @@ impl Flow for BlockFlow {
         );
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         (*mutator)(&mut self.fragment)
     }
 
diff --git a/components/layout/context.rs b/components/layout/context.rs
index 1ab4637cd8a..08530e74a5c 100644
--- a/components/layout/context.rs
+++ b/components/layout/context.rs
@@ -64,7 +64,7 @@ pub struct LayoutContext<'a> {
     pub style_context: SharedStyleContext<'a>,
 
     /// Reference to the script thread image cache.
-    pub image_cache: Arc<ImageCache>,
+    pub image_cache: Arc<dyn ImageCache>,
 
     /// Interface to the font cache thread.
     pub font_cache_thread: Mutex<FontCacheThread>,
@@ -77,7 +77,7 @@ pub struct LayoutContext<'a> {
     >,
 
     /// Paint worklets
-    pub registered_painters: &'a RegisteredPainters,
+    pub registered_painters: &'a dyn RegisteredPainters,
 
     /// A list of in-progress image loads to be shared with the script thread.
     /// A None value means that this layout was not initiated by the script thread.
@@ -197,5 +197,5 @@ pub trait RegisteredPainter: RegisteredSpeculativePainter + Painter {}
 /// A set of registered painters
 pub trait RegisteredPainters: Sync {
     /// Look up a painter
-    fn get(&self, name: &Atom) -> Option<&RegisteredPainter>;
+    fn get(&self, name: &Atom) -> Option<&dyn RegisteredPainter>;
 }
diff --git a/components/layout/flex.rs b/components/layout/flex.rs
index 42cf2c454fe..fe9d72fa55e 100644
--- a/components/layout/flex.rs
+++ b/components/layout/flex.rs
@@ -116,7 +116,7 @@ struct FlexItem {
 }
 
 impl FlexItem {
-    pub fn new(index: usize, flow: &Flow) -> FlexItem {
+    pub fn new(index: usize, flow: &dyn Flow) -> FlexItem {
         let style = &flow.as_block().fragment.style;
         let flex_grow = style.get_position().flex_grow;
         let flex_shrink = style.get_position().flex_shrink;
@@ -140,7 +140,7 @@ impl FlexItem {
     /// Initialize the used flex base size, minimal main size and maximal main size.
     /// For block mode container this method should be called in assign_block_size()
     /// pass so that the item has already been layouted.
-    pub fn init_sizes(&mut self, flow: &mut Flow, containing_length: Au, direction: Direction) {
+    pub fn init_sizes(&mut self, flow: &mut dyn Flow, containing_length: Au, direction: Direction) {
         let block = flow.as_mut_block();
         match direction {
             // TODO(stshine): the definition of min-{width, height} in style component
@@ -207,7 +207,7 @@ impl FlexItem {
 
     /// Returns the outer main size of the item, including paddings and margins,
     /// clamped by max and min size.
-    pub fn outer_main_size(&self, flow: &Flow, direction: Direction) -> Au {
+    pub fn outer_main_size(&self, flow: &dyn Flow, direction: Direction) -> Au {
         let ref fragment = flow.as_block().fragment;
         let outer_width = match direction {
             Direction::Inline => {
@@ -223,7 +223,7 @@ impl FlexItem {
     }
 
     /// Returns the number of auto margins in given direction.
-    pub fn auto_margin_count(&self, flow: &Flow, direction: Direction) -> i32 {
+    pub fn auto_margin_count(&self, flow: &dyn Flow, direction: Direction) -> i32 {
         let margin = flow.as_block().fragment.style.logical_margin();
         let mut margin_count = 0;
         match direction {
@@ -577,7 +577,7 @@ impl FlexFlow {
 
         debug!("content_inline_size = {:?}", content_inline_size);
 
-        let child_count = ImmutableFlowUtils::child_count(self as &Flow) as i32;
+        let child_count = ImmutableFlowUtils::child_count(self as &dyn Flow) as i32;
         debug!("child_count = {:?}", child_count);
         if child_count == 0 {
             return;
@@ -1055,7 +1055,7 @@ impl Flow for FlexFlow {
                     CollapsibleMargins::Collapse(block_start, block_end);
 
                 // TODO(stshine): assign proper static position for absolute descendants.
-                if (&*self as &Flow).contains_roots_of_absolute_flow_tree() {
+                if (&*self as &dyn Flow).contains_roots_of_absolute_flow_tree() {
                     // Assign block-sizes for all flows in this absolute flow tree.
                     // This is preorder because the block-size of an absolute flow may depend on
                     // the block-size of its containing block, which may also be an absolute flow.
@@ -1124,7 +1124,7 @@ impl Flow for FlexFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -1135,7 +1135,7 @@ impl Flow for FlexFlow {
         );
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator);
     }
 }
diff --git a/components/layout/floats.rs b/components/layout/floats.rs
index 88e5eb1d5ea..b054cccceaf 100644
--- a/components/layout/floats.rs
+++ b/components/layout/floats.rs
@@ -494,7 +494,7 @@ impl SpeculatedFloatPlacement {
 
     /// Given the speculated inline size of the floats out for the inorder predecessor of this
     /// flow, computes the speculated inline size of the floats flowing in.
-    pub fn compute_floats_in(&mut self, flow: &mut Flow) {
+    pub fn compute_floats_in(&mut self, flow: &mut dyn Flow) {
         let base_flow = flow.base();
         if base_flow.flags.contains(FlowFlags::CLEARS_LEFT) {
             self.left = Au(0)
@@ -506,7 +506,7 @@ impl SpeculatedFloatPlacement {
 
     /// Given the speculated inline size of the floats out for this flow's last child, computes the
     /// speculated inline size of the floats out for this flow.
-    pub fn compute_floats_out(&mut self, flow: &mut Flow) {
+    pub fn compute_floats_out(&mut self, flow: &mut dyn Flow) {
         if flow.is_block_like() {
             let block_flow = flow.as_block();
             if block_flow.formatting_context_type() != FormattingContextType::None {
@@ -564,7 +564,9 @@ impl SpeculatedFloatPlacement {
     }
 
     /// Given a flow, computes the speculated inline size of the floats in of its first child.
-    pub fn compute_floats_in_for_first_child(parent_flow: &mut Flow) -> SpeculatedFloatPlacement {
+    pub fn compute_floats_in_for_first_child(
+        parent_flow: &mut dyn Flow,
+    ) -> SpeculatedFloatPlacement {
         if !parent_flow.is_block_like() {
             return parent_flow.base().speculated_float_placement_in;
         }
diff --git a/components/layout/flow.rs b/components/layout/flow.rs
index fea1c94f89d..4bf7622636c 100644
--- a/components/layout/flow.rs
+++ b/components/layout/flow.rs
@@ -255,7 +255,7 @@ pub trait Flow: HasBaseFlow + fmt::Debug + Sync + Send + 'static {
         &mut self,
         layout_context: &LayoutContext,
         _fragmentation_context: Option<FragmentationContext>,
-    ) -> Option<Arc<Flow>> {
+    ) -> Option<Arc<dyn Flow>> {
         fn recursive_assign_block_size<F: ?Sized + Flow + GetBaseFlow>(
             flow: &mut F,
             ctx: &LayoutContext,
@@ -423,13 +423,13 @@ pub trait Flow: HasBaseFlow + fmt::Debug + Sync + Send + 'static {
     /// depth of the flow tree during fragment iteration.
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     );
 
     /// Mutably iterates through fragments in this flow.
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment));
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment));
 
     fn compute_collapsible_block_start_margin(
         &mut self,
@@ -813,8 +813,8 @@ pub struct AbsoluteDescendantIter<'a> {
 }
 
 impl<'a> Iterator for AbsoluteDescendantIter<'a> {
-    type Item = &'a mut Flow;
-    fn next(&mut self) -> Option<&'a mut Flow> {
+    type Item = &'a mut dyn Flow;
+    fn next(&mut self) -> Option<&'a mut dyn Flow> {
         self.iter
             .next()
             .map(|info| FlowRef::deref_mut(&mut info.flow))
@@ -1245,7 +1245,7 @@ impl BaseFlow {
     }
 }
 
-impl<'a> ImmutableFlowUtils for &'a Flow {
+impl<'a> ImmutableFlowUtils for &'a dyn Flow {
     /// Returns true if this flow is a block flow or subclass thereof.
     fn is_block_like(self) -> bool {
         self.class().is_block_like()
@@ -1419,7 +1419,7 @@ impl<'a> ImmutableFlowUtils for &'a Flow {
     }
 }
 
-impl<'a> MutableFlowUtils for &'a mut Flow {
+impl<'a> MutableFlowUtils for &'a mut dyn Flow {
     /// Calls `repair_style` and `bubble_inline_sizes`. You should use this method instead of
     /// calling them individually, since there is no reason not to perform both operations.
     fn repair_style_and_bubble_inline_sizes(self, style: &crate::ServoArc<ComputedValues>) {
@@ -1550,8 +1550,8 @@ impl ContainingBlockLink {
 pub struct OpaqueFlow(pub usize);
 
 impl OpaqueFlow {
-    pub fn from_flow(flow: &Flow) -> OpaqueFlow {
-        let object_ptr: *const Flow = flow;
+    pub fn from_flow(flow: &dyn Flow) -> OpaqueFlow {
+        let object_ptr: *const dyn Flow = flow;
         let data_ptr = object_ptr as *const ();
         OpaqueFlow(data_ptr as usize)
     }
diff --git a/components/layout/flow_list.rs b/components/layout/flow_list.rs
index c24734a5a7d..07b42f19a9d 100644
--- a/components/layout/flow_list.rs
+++ b/components/layout/flow_list.rs
@@ -69,11 +69,11 @@ impl FlowList {
         self.flows.push_back(new_tail);
     }
 
-    pub fn push_back_arc(&mut self, new_head: Arc<Flow>) {
+    pub fn push_back_arc(&mut self, new_head: Arc<dyn Flow>) {
         self.flows.push_back(FlowRef::new(new_head));
     }
 
-    pub fn back(&self) -> Option<&Flow> {
+    pub fn back(&self) -> Option<&dyn Flow> {
         self.flows.back().map(|x| &**x)
     }
 
@@ -84,15 +84,15 @@ impl FlowList {
         self.flows.push_front(new_head);
     }
 
-    pub fn push_front_arc(&mut self, new_head: Arc<Flow>) {
+    pub fn push_front_arc(&mut self, new_head: Arc<dyn Flow>) {
         self.flows.push_front(FlowRef::new(new_head));
     }
 
-    pub fn pop_front_arc(&mut self) -> Option<Arc<Flow>> {
+    pub fn pop_front_arc(&mut self) -> Option<Arc<dyn Flow>> {
         self.flows.pop_front().map(FlowRef::into_arc)
     }
 
-    pub fn front(&self) -> Option<&Flow> {
+    pub fn front(&self) -> Option<&dyn Flow> {
         self.flows.front().map(|x| &**x)
     }
 
@@ -161,21 +161,21 @@ impl FlowList {
 }
 
 impl<'a> DoubleEndedIterator for FlowListIterator<'a> {
-    fn next_back(&mut self) -> Option<&'a Flow> {
+    fn next_back(&mut self) -> Option<&'a dyn Flow> {
         self.it.next_back().map(Deref::deref)
     }
 }
 
 impl<'a> DoubleEndedIterator for MutFlowListIterator<'a> {
-    fn next_back(&mut self) -> Option<&'a mut Flow> {
+    fn next_back(&mut self) -> Option<&'a mut dyn Flow> {
         self.it.next_back().map(FlowRef::deref_mut)
     }
 }
 
 impl<'a> Iterator for FlowListIterator<'a> {
-    type Item = &'a Flow;
+    type Item = &'a dyn Flow;
     #[inline]
-    fn next(&mut self) -> Option<&'a Flow> {
+    fn next(&mut self) -> Option<&'a dyn Flow> {
         self.it.next().map(Deref::deref)
     }
 
@@ -186,9 +186,9 @@ impl<'a> Iterator for FlowListIterator<'a> {
 }
 
 impl<'a> Iterator for MutFlowListIterator<'a> {
-    type Item = &'a mut Flow;
+    type Item = &'a mut dyn Flow;
     #[inline]
-    fn next(&mut self) -> Option<&'a mut Flow> {
+    fn next(&mut self) -> Option<&'a mut dyn Flow> {
         self.it.next().map(FlowRef::deref_mut)
     }
 
@@ -206,7 +206,7 @@ pub struct FlowListRandomAccessMut<'a> {
 }
 
 impl<'a> FlowListRandomAccessMut<'a> {
-    pub fn get<'b>(&'b mut self, index: usize) -> &'b mut Flow {
+    pub fn get<'b>(&'b mut self, index: usize) -> &'b mut dyn Flow {
         while index >= self.cache.len() {
             match self.iterator.next() {
                 None => panic!("Flow index out of range!"),
diff --git a/components/layout/flow_ref.rs b/components/layout/flow_ref.rs
index 31748f7039d..6b9027459ee 100644
--- a/components/layout/flow_ref.rs
+++ b/components/layout/flow_ref.rs
@@ -13,11 +13,11 @@ use std::ops::Deref;
 use std::sync::{Arc, Weak};
 
 #[derive(Clone, Debug)]
-pub struct FlowRef(Arc<Flow>);
+pub struct FlowRef(Arc<dyn Flow>);
 
 impl Deref for FlowRef {
-    type Target = Flow;
-    fn deref(&self) -> &Flow {
+    type Target = dyn Flow;
+    fn deref(&self) -> &dyn Flow {
         self.0.deref()
     }
 }
@@ -25,19 +25,19 @@ impl Deref for FlowRef {
 impl FlowRef {
     /// `FlowRef`s can only be made available to the traversal code.
     /// See https://github.com/servo/servo/issues/14014 for more details.
-    pub fn new(mut r: Arc<Flow>) -> Self {
+    pub fn new(mut r: Arc<dyn Flow>) -> Self {
         // This assertion checks that this `FlowRef` does not alias normal `Arc`s.
         // If that happens, we're in trouble.
         assert!(Arc::get_mut(&mut r).is_some());
         FlowRef(r)
     }
-    pub fn get_mut(this: &mut FlowRef) -> Option<&mut Flow> {
+    pub fn get_mut(this: &mut FlowRef) -> Option<&mut dyn Flow> {
         Arc::get_mut(&mut this.0)
     }
     pub fn downgrade(this: &FlowRef) -> WeakFlowRef {
         WeakFlowRef(Arc::downgrade(&this.0))
     }
-    pub fn into_arc(mut this: FlowRef) -> Arc<Flow> {
+    pub fn into_arc(mut this: FlowRef) -> Arc<dyn Flow> {
         // This assertion checks that this `FlowRef` does not alias normal `Arc`s.
         // If that happens, we're in trouble.
         assert!(FlowRef::get_mut(&mut this).is_some());
@@ -48,14 +48,14 @@ impl FlowRef {
     /// See https://github.com/servo/servo/issues/6503
     /// Use Arc::get_mut instead when possible (e.g. on an Arc that was just created).
     #[allow(unsafe_code)]
-    pub fn deref_mut(this: &mut FlowRef) -> &mut Flow {
-        let ptr: *const Flow = &*this.0;
-        unsafe { &mut *(ptr as *mut Flow) }
+    pub fn deref_mut(this: &mut FlowRef) -> &mut dyn Flow {
+        let ptr: *const dyn Flow = &*this.0;
+        unsafe { &mut *(ptr as *mut dyn Flow) }
     }
 }
 
 #[derive(Clone, Debug)]
-pub struct WeakFlowRef(Weak<Flow>);
+pub struct WeakFlowRef(Weak<dyn Flow>);
 
 impl WeakFlowRef {
     pub fn upgrade(&self) -> Option<FlowRef> {
diff --git a/components/layout/generated_content.rs b/components/layout/generated_content.rs
index 024d51b22fb..af710142446 100644
--- a/components/layout/generated_content.rs
+++ b/components/layout/generated_content.rs
@@ -152,7 +152,7 @@ impl<'a> ResolveGeneratedContent<'a> {
 
 impl<'a> InorderFlowTraversal for ResolveGeneratedContent<'a> {
     #[inline]
-    fn process(&mut self, flow: &mut Flow, level: u32) {
+    fn process(&mut self, flow: &mut dyn Flow, level: u32) {
         let mut mutator = ResolveGeneratedContentFragmentMutator {
             traversal: self,
             level: level,
@@ -163,7 +163,7 @@ impl<'a> InorderFlowTraversal for ResolveGeneratedContent<'a> {
     }
 
     #[inline]
-    fn should_process_subtree(&mut self, flow: &mut Flow) -> bool {
+    fn should_process_subtree(&mut self, flow: &mut dyn Flow) -> bool {
         flow.base()
             .restyle_damage
             .intersects(ServoRestyleDamage::RESOLVE_GENERATED_CONTENT) ||
diff --git a/components/layout/incremental.rs b/components/layout/incremental.rs
index 6734620e5a0..7dde93384b7 100644
--- a/components/layout/incremental.rs
+++ b/components/layout/incremental.rs
@@ -27,7 +27,7 @@ pub trait LayoutDamageComputation {
     fn reflow_entire_document(self);
 }
 
-impl<'a> LayoutDamageComputation for &'a mut Flow {
+impl<'a> LayoutDamageComputation for &'a mut dyn Flow {
     fn compute_layout_damage(self) -> SpecialRestyleDamage {
         let mut special_damage = SpecialRestyleDamage::empty();
         let is_absolutely_positioned = self
@@ -53,7 +53,7 @@ impl<'a> LayoutDamageComputation for &'a mut Flow {
                         .damage_for_child(is_absolutely_positioned, child_is_absolutely_positioned),
                 );
                 {
-                    let kid: &mut Flow = kid;
+                    let kid: &mut dyn Flow = kid;
                     special_damage.insert(kid.compute_layout_damage());
                 }
                 self_base.restyle_damage.insert(
diff --git a/components/layout/inline.rs b/components/layout/inline.rs
index 08a371bac08..080c68129a2 100644
--- a/components/layout/inline.rs
+++ b/components/layout/inline.rs
@@ -1854,7 +1854,7 @@ impl Flow for InlineFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -1888,7 +1888,7 @@ impl Flow for InlineFlow {
         }
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         for fragment in &mut self.fragments.fragments {
             (*mutator)(fragment)
         }
diff --git a/components/layout/lib.rs b/components/layout/lib.rs
index b91ee22eba8..2bf13e32173 100644
--- a/components/layout/lib.rs
+++ b/components/layout/lib.rs
@@ -4,49 +4,16 @@
 
 #![deny(unsafe_code)]
 
-extern crate app_units;
-extern crate atomic_refcell;
 #[macro_use]
 extern crate bitflags;
-extern crate canvas_traits;
-extern crate euclid;
-extern crate fnv;
-extern crate fxhash;
-extern crate gfx;
-extern crate gfx_traits;
 #[macro_use]
 extern crate html5ever;
-extern crate ipc_channel;
-extern crate libc;
 #[macro_use]
 extern crate log;
-extern crate malloc_size_of;
-extern crate msg;
-extern crate net_traits;
-extern crate ordered_float;
-extern crate parking_lot;
-extern crate profile_traits;
 #[macro_use]
 extern crate range;
-extern crate rayon;
-extern crate script_layout_interface;
-extern crate script_traits;
 #[macro_use]
 extern crate serde;
-extern crate serde_json;
-extern crate servo_arc;
-extern crate servo_atoms;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_geometry;
-extern crate servo_url;
-extern crate smallvec;
-extern crate style;
-extern crate style_traits;
-extern crate unicode_bidi;
-extern crate unicode_script;
-extern crate webrender_api;
-extern crate xi_unicode;
 
 #[macro_use]
 pub mod layout_debug;
diff --git a/components/layout/list_item.rs b/components/layout/list_item.rs
index cef1487f2f0..893b63fb66a 100644
--- a/components/layout/list_item.rs
+++ b/components/layout/list_item.rs
@@ -231,7 +231,7 @@ impl Flow for ListItemFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -266,7 +266,7 @@ impl Flow for ListItemFlow {
         }
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator);
 
         for marker in &mut self.marker_fragments {
diff --git a/components/layout/multicol.rs b/components/layout/multicol.rs
index 71d9befac61..0d2a72a7b3b 100644
--- a/components/layout/multicol.rs
+++ b/components/layout/multicol.rs
@@ -241,7 +241,7 @@ impl Flow for MulticolFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -252,7 +252,7 @@ impl Flow for MulticolFlow {
         );
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator);
     }
 
@@ -295,7 +295,7 @@ impl Flow for MulticolColumnFlow {
         &mut self,
         layout_context: &LayoutContext,
         fragmentation_context: Option<FragmentationContext>,
-    ) -> Option<Arc<Flow>> {
+    ) -> Option<Arc<dyn Flow>> {
         Flow::fragment(&mut self.block_flow, layout_context, fragmentation_context)
     }
 
@@ -345,7 +345,7 @@ impl Flow for MulticolColumnFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -356,7 +356,7 @@ impl Flow for MulticolColumnFlow {
         );
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator);
     }
 
diff --git a/components/layout/parallel.rs b/components/layout/parallel.rs
index f510851ce92..3a5a956e28c 100644
--- a/components/layout/parallel.rs
+++ b/components/layout/parallel.rs
@@ -29,7 +29,7 @@ pub type FlowList = SmallVec<[UnsafeFlow; CHUNK_SIZE]>;
 
 /// Vtable + pointer representation of a Flow trait object.
 #[derive(Clone, Copy, Eq, PartialEq)]
-pub struct UnsafeFlow(*const Flow);
+pub struct UnsafeFlow(*const dyn Flow);
 
 unsafe impl Sync for UnsafeFlow {}
 unsafe impl Send for UnsafeFlow {}
@@ -73,7 +73,7 @@ impl FlowParallelInfo {
 fn bottom_up_flow(mut unsafe_flow: UnsafeFlow, assign_bsize_traversal: &AssignBSizes) {
     loop {
         // Get a real flow.
-        let flow: &mut Flow = unsafe { mem::transmute(unsafe_flow) };
+        let flow: &mut dyn Flow = unsafe { mem::transmute(unsafe_flow) };
 
         // Perform the appropriate traversal.
         if assign_bsize_traversal.should_process(flow) {
@@ -97,7 +97,7 @@ fn bottom_up_flow(mut unsafe_flow: UnsafeFlow, assign_bsize_traversal: &AssignBS
         // No, we're not at the root yet. Then are we the last child
         // of our parent to finish processing? If so, we can continue
         // on with our parent; otherwise, we've gotta wait.
-        let parent: &mut Flow = unsafe { &mut *(unsafe_parent.0 as *mut Flow) };
+        let parent: &mut dyn Flow = unsafe { &mut *(unsafe_parent.0 as *mut dyn Flow) };
         let parent_base = parent.mut_base();
         if parent_base
             .parallel
@@ -127,7 +127,7 @@ fn top_down_flow<'scope>(
         let mut had_children = false;
         unsafe {
             // Get a real flow.
-            let flow: &mut Flow = mem::transmute(*unsafe_flow);
+            let flow: &mut dyn Flow = mem::transmute(*unsafe_flow);
             flow.mut_base().thread_id = pool.current_thread_index().unwrap() as u8;
 
             if assign_isize_traversal.should_process(flow) {
@@ -191,7 +191,7 @@ fn top_down_flow<'scope>(
 
 /// Run the main layout passes in parallel.
 pub fn reflow(
-    root: &mut Flow,
+    root: &mut dyn Flow,
     profiler_metadata: Option<TimerMetadata>,
     time_profiler_chan: time::ProfilerChan,
     context: &LayoutContext,
diff --git a/components/layout/persistent_list.rs b/components/layout/persistent_list.rs
index 0a8337bfaa7..735b2407ae5 100644
--- a/components/layout/persistent_list.rs
+++ b/components/layout/persistent_list.rs
@@ -77,7 +77,7 @@ where
 
 pub struct PersistentListIterator<'a, T>
 where
-    T: 'a + Send + Sync,
+    T: Send + Sync,
 {
     entry: Option<&'a PersistentListEntry<T>>,
 }
diff --git a/components/layout/query.rs b/components/layout/query.rs
index 7a6a85824ed..1255e65bcbd 100644
--- a/components/layout/query.rs
+++ b/components/layout/query.rs
@@ -366,7 +366,7 @@ impl FragmentBorderBoxIterator for MarginRetrievingFragmentBorderBoxIterator {
 
 pub fn process_content_box_request<N: LayoutNode>(
     requested_node: N,
-    layout_root: &mut Flow,
+    layout_root: &mut dyn Flow,
 ) -> Option<Rect<Au>> {
     // FIXME(pcwalton): This has not been updated to handle the stacking context relative
     // stuff. So the position is wrong in most cases.
@@ -377,7 +377,7 @@ pub fn process_content_box_request<N: LayoutNode>(
 
 pub fn process_content_boxes_request<N: LayoutNode>(
     requested_node: N,
-    layout_root: &mut Flow,
+    layout_root: &mut dyn Flow,
 ) -> Vec<Rect<Au>> {
     // FIXME(pcwalton): This has not been updated to handle the stacking context relative
     // stuff. So the position is wrong in most cases.
@@ -671,7 +671,7 @@ impl FragmentBorderBoxIterator for ParentOffsetBorderBoxIterator {
 
 pub fn process_node_geometry_request<N: LayoutNode>(
     requested_node: N,
-    layout_root: &mut Flow,
+    layout_root: &mut dyn Flow,
 ) -> Rect<i32> {
     let mut iterator = FragmentLocatingFragmentIterator::new(requested_node.opaque());
     sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
@@ -689,7 +689,7 @@ pub fn process_node_scroll_id_request<N: LayoutNode>(
 /// https://drafts.csswg.org/cssom-view/#scrolling-area
 pub fn process_node_scroll_area_request<N: LayoutNode>(
     requested_node: N,
-    layout_root: &mut Flow,
+    layout_root: &mut dyn Flow,
 ) -> Rect<i32> {
     let mut iterator = UnioningFragmentScrollAreaIterator::new(requested_node.opaque());
     sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
@@ -742,7 +742,7 @@ pub fn process_resolved_style_request<'a, N>(
     node: N,
     pseudo: &Option<PseudoElement>,
     property: &PropertyId,
-    layout_root: &mut Flow,
+    layout_root: &mut dyn Flow,
 ) -> String
 where
     N: LayoutNode,
@@ -791,7 +791,7 @@ fn process_resolved_style_request_internal<'a, N>(
     requested_node: N,
     pseudo: &Option<PseudoElement>,
     property: &PropertyId,
-    layout_root: &mut Flow,
+    layout_root: &mut dyn Flow,
 ) -> String
 where
     N: LayoutNode,
@@ -843,7 +843,7 @@ where
 
     fn used_value_for_position_property<N: LayoutNode>(
         layout_el: <N::ConcreteThreadSafeLayoutNode as ThreadSafeLayoutNode>::ConcreteThreadSafeLayoutElement,
-        layout_root: &mut Flow,
+        layout_root: &mut dyn Flow,
         requested_node: N,
         longhand_id: LonghandId,
     ) -> String {
@@ -934,7 +934,7 @@ where
 
 pub fn process_offset_parent_query<N: LayoutNode>(
     requested_node: N,
-    layout_root: &mut Flow,
+    layout_root: &mut dyn Flow,
 ) -> OffsetParentResponse {
     let mut iterator = ParentOffsetBorderBoxIterator::new(requested_node.opaque());
     sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
diff --git a/components/layout/sequential.rs b/components/layout/sequential.rs
index 3203dee5e49..9ade33d97a7 100644
--- a/components/layout/sequential.rs
+++ b/components/layout/sequential.rs
@@ -19,14 +19,14 @@ use servo_config::opts;
 use style::servo::restyle_damage::ServoRestyleDamage;
 use webrender_api::LayoutPoint;
 
-pub fn resolve_generated_content(root: &mut Flow, layout_context: &LayoutContext) {
+pub fn resolve_generated_content(root: &mut dyn Flow, layout_context: &LayoutContext) {
     ResolveGeneratedContent::new(&layout_context).traverse(root, 0);
 }
 
 /// Run the main layout passes sequentially.
-pub fn reflow(root: &mut Flow, layout_context: &LayoutContext, relayout_mode: RelayoutMode) {
+pub fn reflow(root: &mut dyn Flow, layout_context: &LayoutContext, relayout_mode: RelayoutMode) {
     fn doit(
-        flow: &mut Flow,
+        flow: &mut dyn Flow,
         assign_inline_sizes: AssignISizes,
         assign_block_sizes: AssignBSizes,
         relayout_mode: RelayoutMode,
@@ -70,7 +70,7 @@ pub fn reflow(root: &mut Flow, layout_context: &LayoutContext, relayout_mode: Re
 }
 
 pub fn build_display_list_for_subtree<'a>(
-    flow_root: &mut Flow,
+    flow_root: &mut dyn Flow,
     layout_context: &'a LayoutContext,
 ) -> DisplayListBuildState<'a> {
     let mut state = StackingContextCollectionState::new(layout_context.id);
@@ -83,13 +83,13 @@ pub fn build_display_list_for_subtree<'a>(
 }
 
 pub fn iterate_through_flow_tree_fragment_border_boxes(
-    root: &mut Flow,
-    iterator: &mut FragmentBorderBoxIterator,
+    root: &mut dyn Flow,
+    iterator: &mut dyn FragmentBorderBoxIterator,
 ) {
     fn doit(
-        flow: &mut Flow,
+        flow: &mut dyn Flow,
         level: i32,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         stacking_context_position: &Point2D<Au>,
     ) {
         flow.iterate_through_fragment_border_boxes(iterator, level, stacking_context_position);
@@ -119,7 +119,7 @@ pub fn iterate_through_flow_tree_fragment_border_boxes(
     doit(root, 0, iterator, &Point2D::zero());
 }
 
-pub fn store_overflow(layout_context: &LayoutContext, flow: &mut Flow) {
+pub fn store_overflow(layout_context: &LayoutContext, flow: &mut dyn Flow) {
     if !flow
         .base()
         .restyle_damage
@@ -142,7 +142,7 @@ pub fn store_overflow(layout_context: &LayoutContext, flow: &mut Flow) {
 /// Guesses how much inline size will be taken up by floats on the left and right sides of the
 /// given flow. This is needed to speculatively calculate the inline sizes of block formatting
 /// contexts. The speculation typically succeeds, but if it doesn't we have to lay it out again.
-pub fn guess_float_placement(flow: &mut Flow) {
+pub fn guess_float_placement(flow: &mut dyn Flow) {
     if !flow
         .base()
         .restyle_damage
diff --git a/components/layout/table.rs b/components/layout/table.rs
index 4f28b22e6f6..10917628e75 100644
--- a/components/layout/table.rs
+++ b/components/layout/table.rs
@@ -611,7 +611,7 @@ impl Flow for TableFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -622,7 +622,7 @@ impl Flow for TableFlow {
         )
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator)
     }
 
diff --git a/components/layout/table_caption.rs b/components/layout/table_caption.rs
index a9d9660144f..910ad7f8c5b 100644
--- a/components/layout/table_caption.rs
+++ b/components/layout/table_caption.rs
@@ -115,7 +115,7 @@ impl Flow for TableCaptionFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -126,7 +126,7 @@ impl Flow for TableCaptionFlow {
         )
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator)
     }
 
diff --git a/components/layout/table_cell.rs b/components/layout/table_cell.rs
index 51442f2f832..879ab9b82a1 100644
--- a/components/layout/table_cell.rs
+++ b/components/layout/table_cell.rs
@@ -334,7 +334,7 @@ impl Flow for TableCellFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -345,7 +345,7 @@ impl Flow for TableCellFlow {
         )
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator)
     }
 
diff --git a/components/layout/table_colgroup.rs b/components/layout/table_colgroup.rs
index d1347ef4cce..b2fd17d1978 100644
--- a/components/layout/table_colgroup.rs
+++ b/components/layout/table_colgroup.rs
@@ -112,13 +112,13 @@ impl Flow for TableColGroupFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        _: &mut FragmentBorderBoxIterator,
+        _: &mut dyn FragmentBorderBoxIterator,
         _: i32,
         _: &Point2D<Au>,
     ) {
     }
 
-    fn mutate_fragments(&mut self, _: &mut FnMut(&mut Fragment)) {}
+    fn mutate_fragments(&mut self, _: &mut dyn FnMut(&mut Fragment)) {}
 }
 
 impl fmt::Debug for TableColGroupFlow {
diff --git a/components/layout/table_row.rs b/components/layout/table_row.rs
index 5b50b48448e..ba327bd266b 100644
--- a/components/layout/table_row.rs
+++ b/components/layout/table_row.rs
@@ -650,7 +650,7 @@ impl Flow for TableRowFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -661,7 +661,7 @@ impl Flow for TableRowFlow {
         )
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator)
     }
 
@@ -907,7 +907,7 @@ impl CollapsedBorder {
 
 /// Pushes column inline size, incoming rowspan, and border collapse info down to a child.
 pub fn propagate_column_inline_sizes_to_child(
-    child_flow: &mut Flow,
+    child_flow: &mut dyn Flow,
     table_writing_mode: WritingMode,
     column_computed_inline_sizes: &[ColumnComputedInlineSize],
     border_spacing: &BorderSpacing,
@@ -975,7 +975,7 @@ pub fn propagate_column_inline_sizes_to_child(
 
 /// Lay out table cells inline according to the computer column sizes.
 fn set_inline_position_of_child_flow(
-    child_flow: &mut Flow,
+    child_flow: &mut dyn Flow,
     child_index: usize,
     column_index: &mut usize,
     incoming_rowspan: &[u32],
diff --git a/components/layout/table_rowgroup.rs b/components/layout/table_rowgroup.rs
index 703bd9217a0..947bfde2d64 100644
--- a/components/layout/table_rowgroup.rs
+++ b/components/layout/table_rowgroup.rs
@@ -246,7 +246,7 @@ impl Flow for TableRowGroupFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -257,7 +257,7 @@ impl Flow for TableRowGroupFlow {
         )
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator)
     }
 
diff --git a/components/layout/table_wrapper.rs b/components/layout/table_wrapper.rs
index ad6bee3b4e3..12683ee8946 100644
--- a/components/layout/table_wrapper.rs
+++ b/components/layout/table_wrapper.rs
@@ -531,7 +531,7 @@ impl Flow for TableWrapperFlow {
 
     fn iterate_through_fragment_border_boxes(
         &self,
-        iterator: &mut FragmentBorderBoxIterator,
+        iterator: &mut dyn FragmentBorderBoxIterator,
         level: i32,
         stacking_context_position: &Point2D<Au>,
     ) {
@@ -542,7 +542,7 @@ impl Flow for TableWrapperFlow {
         )
     }
 
-    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
+    fn mutate_fragments(&mut self, mutator: &mut dyn FnMut(&mut Fragment)) {
         self.block_flow.mutate_fragments(mutator)
     }
 
diff --git a/components/layout/tests/size_of.rs b/components/layout/tests/size_of.rs
index 7d869271368..430053ca160 100644
--- a/components/layout/tests/size_of.rs
+++ b/components/layout/tests/size_of.rs
@@ -4,7 +4,6 @@
 
 #![cfg(target_pointer_width = "64")]
 
-extern crate layout;
 #[macro_use]
 extern crate size_of_test;
 
diff --git a/components/layout/traversal.rs b/components/layout/traversal.rs
index 51888069cac..6e2e739d8db 100644
--- a/components/layout/traversal.rs
+++ b/components/layout/traversal.rs
@@ -90,23 +90,23 @@ where
 /// A top-down traversal.
 pub trait PreorderFlowTraversal {
     /// The operation to perform. Return true to continue or false to stop.
-    fn process(&self, flow: &mut Flow);
+    fn process(&self, flow: &mut dyn Flow);
 
     /// Returns true if this node should be processed and false if neither this node nor its
     /// descendants should be processed.
-    fn should_process_subtree(&self, _flow: &mut Flow) -> bool {
+    fn should_process_subtree(&self, _flow: &mut dyn Flow) -> bool {
         true
     }
 
     /// Returns true if this node must be processed in-order. If this returns false,
     /// we skip the operation for this node, but continue processing the descendants.
     /// This is called *after* parent nodes are visited.
-    fn should_process(&self, _flow: &mut Flow) -> bool {
+    fn should_process(&self, _flow: &mut dyn Flow) -> bool {
         true
     }
 
     /// Traverses the tree in preorder.
-    fn traverse(&self, flow: &mut Flow) {
+    fn traverse(&self, flow: &mut dyn Flow) {
         if !self.should_process_subtree(flow) {
             return;
         }
@@ -124,7 +124,7 @@ pub trait PreorderFlowTraversal {
     /// their direct absolute descendants.
     ///
     /// Return true if the traversal is to continue or false to stop.
-    fn traverse_absolute_flows(&self, flow: &mut Flow) {
+    fn traverse_absolute_flows(&self, flow: &mut dyn Flow) {
         if self.should_process(flow) {
             self.process(flow);
         }
@@ -137,17 +137,17 @@ pub trait PreorderFlowTraversal {
 /// A bottom-up traversal, with a optional in-order pass.
 pub trait PostorderFlowTraversal {
     /// The operation to perform. Return true to continue or false to stop.
-    fn process(&self, flow: &mut Flow);
+    fn process(&self, flow: &mut dyn Flow);
 
     /// Returns false if this node must be processed in-order. If this returns false, we skip the
     /// operation for this node, but continue processing the ancestors. This is called *after*
     /// child nodes are visited.
-    fn should_process(&self, _flow: &mut Flow) -> bool {
+    fn should_process(&self, _flow: &mut dyn Flow) -> bool {
         true
     }
 
     /// Traverses the tree in postorder.
-    fn traverse(&self, flow: &mut Flow) {
+    fn traverse(&self, flow: &mut dyn Flow) {
         for kid in flow.mut_base().child_iter_mut() {
             self.traverse(kid);
         }
@@ -160,16 +160,16 @@ pub trait PostorderFlowTraversal {
 /// An in-order (sequential only) traversal.
 pub trait InorderFlowTraversal {
     /// The operation to perform. Returns the level of the tree we're at.
-    fn process(&mut self, flow: &mut Flow, level: u32);
+    fn process(&mut self, flow: &mut dyn Flow, level: u32);
 
     /// Returns true if this node should be processed and false if neither this node nor its
     /// descendants should be processed.
-    fn should_process_subtree(&mut self, _flow: &mut Flow) -> bool {
+    fn should_process_subtree(&mut self, _flow: &mut dyn Flow) -> bool {
         true
     }
 
     /// Traverses the tree in-order.
-    fn traverse(&mut self, flow: &mut Flow, level: u32) {
+    fn traverse(&mut self, flow: &mut dyn Flow, level: u32) {
         if !self.should_process_subtree(flow) {
             return;
         }
@@ -238,7 +238,7 @@ pub struct BubbleISizes<'a> {
 
 impl<'a> PostorderFlowTraversal for BubbleISizes<'a> {
     #[inline]
-    fn process(&self, flow: &mut Flow) {
+    fn process(&self, flow: &mut dyn Flow) {
         flow.bubble_inline_sizes();
         flow.mut_base()
             .restyle_damage
@@ -246,7 +246,7 @@ impl<'a> PostorderFlowTraversal for BubbleISizes<'a> {
     }
 
     #[inline]
-    fn should_process(&self, flow: &mut Flow) -> bool {
+    fn should_process(&self, flow: &mut dyn Flow) -> bool {
         flow.base()
             .restyle_damage
             .contains(ServoRestyleDamage::BUBBLE_ISIZES)
@@ -261,12 +261,12 @@ pub struct AssignISizes<'a> {
 
 impl<'a> PreorderFlowTraversal for AssignISizes<'a> {
     #[inline]
-    fn process(&self, flow: &mut Flow) {
+    fn process(&self, flow: &mut dyn Flow) {
         flow.assign_inline_sizes(self.layout_context);
     }
 
     #[inline]
-    fn should_process(&self, flow: &mut Flow) -> bool {
+    fn should_process(&self, flow: &mut dyn Flow) -> bool {
         flow.base()
             .restyle_damage
             .intersects(ServoRestyleDamage::REFLOW_OUT_OF_FLOW | ServoRestyleDamage::REFLOW)
@@ -283,7 +283,7 @@ pub struct AssignBSizes<'a> {
 
 impl<'a> PostorderFlowTraversal for AssignBSizes<'a> {
     #[inline]
-    fn process(&self, flow: &mut Flow) {
+    fn process(&self, flow: &mut dyn Flow) {
         // Can't do anything with anything that floats might flow through until we reach their
         // inorder parent.
         //
@@ -297,7 +297,7 @@ impl<'a> PostorderFlowTraversal for AssignBSizes<'a> {
     }
 
     #[inline]
-    fn should_process(&self, flow: &mut Flow) -> bool {
+    fn should_process(&self, flow: &mut dyn Flow) -> bool {
         let base = flow.base();
         base.restyle_damage.intersects(ServoRestyleDamage::REFLOW_OUT_OF_FLOW | ServoRestyleDamage::REFLOW) &&
         // The fragmentation countainer is responsible for calling
@@ -312,14 +312,14 @@ pub struct ComputeStackingRelativePositions<'a> {
 
 impl<'a> PreorderFlowTraversal for ComputeStackingRelativePositions<'a> {
     #[inline]
-    fn should_process_subtree(&self, flow: &mut Flow) -> bool {
+    fn should_process_subtree(&self, flow: &mut dyn Flow) -> bool {
         flow.base()
             .restyle_damage
             .contains(ServoRestyleDamage::REPOSITION)
     }
 
     #[inline]
-    fn process(&self, flow: &mut Flow) {
+    fn process(&self, flow: &mut dyn Flow) {
         flow.compute_stacking_relative_position(self.layout_context);
         flow.mut_base()
             .restyle_damage
@@ -333,7 +333,7 @@ pub struct BuildDisplayList<'a> {
 
 impl<'a> BuildDisplayList<'a> {
     #[inline]
-    pub fn traverse(&mut self, flow: &mut Flow) {
+    pub fn traverse(&mut self, flow: &mut dyn Flow) {
         let parent_stacking_context_id = self.state.current_stacking_context_id;
         self.state.current_stacking_context_id = flow.base().stacking_context_id;
 
diff --git a/components/layout_thread/lib.rs b/components/layout_thread/lib.rs
index bf10a795732..91b801464fe 100644
--- a/components/layout_thread/lib.rs
+++ b/components/layout_thread/lib.rs
@@ -5,52 +5,18 @@
 //! The layout thread. Performs layout on the DOM, builds display lists and sends them to be
 //! painted.
 
-extern crate app_units;
-extern crate atomic_refcell;
-extern crate embedder_traits;
-extern crate euclid;
-extern crate fnv;
-extern crate fxhash;
-extern crate gfx;
-extern crate gfx_traits;
-extern crate histogram;
 #[macro_use]
 extern crate html5ever;
-extern crate ipc_channel;
 #[macro_use]
 extern crate layout;
-extern crate layout_traits;
 #[macro_use]
 extern crate lazy_static;
-extern crate libc;
 #[macro_use]
 extern crate log;
-extern crate malloc_size_of;
-extern crate metrics;
-extern crate msg;
-extern crate net_traits;
-extern crate parking_lot;
 #[macro_use]
 extern crate profile_traits;
-extern crate range;
-extern crate rayon;
-extern crate script;
-extern crate script_layout_interface;
-extern crate script_traits;
-extern crate selectors;
-extern crate serde_json;
-extern crate servo_allocator;
-extern crate servo_arc;
-extern crate servo_atoms;
 #[macro_use]
 extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_geometry;
-extern crate servo_url;
-extern crate style;
-extern crate style_traits;
-extern crate time as std_time;
-extern crate webrender_api;
 
 mod dom_wrapper;
 
@@ -101,8 +67,8 @@ use msg::constellation_msg::PipelineId;
 use msg::constellation_msg::TopLevelBrowsingContextId;
 use net_traits::image_cache::{ImageCache, UsePlaceholder};
 use parking_lot::RwLock;
-use profile_traits::mem::{self, Report, ReportKind, ReportsChan};
-use profile_traits::time::{self, profile, TimerMetadata};
+use profile_traits::mem::{self as profile_mem, Report, ReportKind, ReportsChan};
+use profile_traits::time::{self as profile_time, profile, TimerMetadata};
 use profile_traits::time::{TimerMetadataFrameType, TimerMetadataReflowType};
 use script_layout_interface::message::{Msg, NewLayoutThreadInfo, NodesFromPointQueryType, Reflow};
 use script_layout_interface::message::{QueryMsg, ReflowComplete, ReflowGoal, ScriptReflow};
@@ -124,7 +90,6 @@ use servo_url::ServoUrl;
 use std::borrow::ToOwned;
 use std::cell::{Cell, RefCell};
 use std::collections::HashMap;
-use std::mem as std_mem;
 use std::ops::{Deref, DerefMut};
 use std::process;
 use std::sync::atomic::{AtomicUsize, Ordering};
@@ -191,13 +156,13 @@ pub struct LayoutThread {
     script_chan: IpcSender<ConstellationControlMsg>,
 
     /// The channel on which messages can be sent to the time profiler.
-    time_profiler_chan: time::ProfilerChan,
+    time_profiler_chan: profile_time::ProfilerChan,
 
     /// The channel on which messages can be sent to the memory profiler.
-    mem_profiler_chan: mem::ProfilerChan,
+    mem_profiler_chan: profile_mem::ProfilerChan,
 
     /// Reference to the script thread image cache.
-    image_cache: Arc<ImageCache>,
+    image_cache: Arc<dyn ImageCache>,
 
     /// Public interface to the font cache thread.
     font_cache_thread: FontCacheThread,
@@ -289,10 +254,10 @@ impl LayoutThreadFactory for LayoutThread {
         pipeline_port: IpcReceiver<LayoutControlMsg>,
         constellation_chan: IpcSender<ConstellationMsg>,
         script_chan: IpcSender<ConstellationControlMsg>,
-        image_cache: Arc<ImageCache>,
+        image_cache: Arc<dyn ImageCache>,
         font_cache_thread: FontCacheThread,
-        time_profiler_chan: time::ProfilerChan,
-        mem_profiler_chan: mem::ProfilerChan,
+        time_profiler_chan: profile_time::ProfilerChan,
+        mem_profiler_chan: profile_mem::ProfilerChan,
         content_process_shutdown_chan: Option<IpcSender<()>>,
         webrender_api_sender: webrender_api::RenderApiSender,
         webrender_document: webrender_api::DocumentId,
@@ -480,10 +445,10 @@ impl LayoutThread {
         pipeline_port: IpcReceiver<LayoutControlMsg>,
         constellation_chan: IpcSender<ConstellationMsg>,
         script_chan: IpcSender<ConstellationControlMsg>,
-        image_cache: Arc<ImageCache>,
+        image_cache: Arc<dyn ImageCache>,
         font_cache_thread: FontCacheThread,
-        time_profiler_chan: time::ProfilerChan,
-        mem_profiler_chan: mem::ProfilerChan,
+        time_profiler_chan: profile_time::ProfilerChan,
+        mem_profiler_chan: profile_mem::ProfilerChan,
         webrender_api_sender: webrender_api::RenderApiSender,
         webrender_document: webrender_api::DocumentId,
         layout_threads: usize,
@@ -716,13 +681,13 @@ impl LayoutThread {
             Msg::SetQuirksMode(mode) => self.handle_set_quirks_mode(mode),
             Msg::GetRPC(response_chan) => {
                 response_chan
-                    .send(Box::new(LayoutRPCImpl(self.rw_data.clone())) as Box<LayoutRPC + Send>)
+                    .send(Box::new(LayoutRPCImpl(self.rw_data.clone())) as Box<dyn LayoutRPC + Send>)
                     .unwrap();
             },
             Msg::Reflow(data) => {
                 let mut data = ScriptReflowResult::new(data);
                 profile(
-                    time::ProfilerCategory::LayoutPerform,
+                    profile_time::ProfilerCategory::LayoutPerform,
                     self.profiler_metadata(),
                     self.time_profiler_chan.clone(),
                     || self.handle_reflow(&mut data, possibly_locked_rw_data),
@@ -812,7 +777,7 @@ impl LayoutThread {
         let mut reports = vec![];
         // Servo uses vanilla jemalloc, which doesn't have a
         // malloc_enclosing_size_of function.
-        let mut ops = MallocSizeOfOps::new(::servo_allocator::usable_size, None, None);
+        let mut ops = MallocSizeOfOps::new(servo_allocator::usable_size, None, None);
 
         // FIXME(njn): Just measuring the display tree for now.
         let rw_data = possibly_locked_rw_data.lock();
@@ -963,7 +928,7 @@ impl LayoutThread {
     /// This corresponds to `Reflow()` in Gecko and `layout()` in WebKit/Blink and should be
     /// benchmarked against those two. It is marked `#[inline(never)]` to aid profiling.
     #[inline(never)]
-    fn solve_constraints(layout_root: &mut Flow, layout_context: &LayoutContext) {
+    fn solve_constraints(layout_root: &mut dyn Flow, layout_context: &LayoutContext) {
         let _scope = layout_debug_scope!("solve_constraints");
         sequential::reflow(layout_root, layout_context, RelayoutMode::Incremental);
     }
@@ -975,9 +940,9 @@ impl LayoutThread {
     #[inline(never)]
     fn solve_constraints_parallel(
         traversal: &rayon::ThreadPool,
-        layout_root: &mut Flow,
+        layout_root: &mut dyn Flow,
         profiler_metadata: Option<TimerMetadata>,
-        time_profiler_chan: time::ProfilerChan,
+        time_profiler_chan: profile_time::ProfilerChan,
         layout_context: &LayoutContext,
     ) {
         let _scope = layout_debug_scope!("solve_constraints_parallel");
@@ -1000,14 +965,14 @@ impl LayoutThread {
         data: &Reflow,
         reflow_goal: &ReflowGoal,
         document: Option<&ServoLayoutDocument>,
-        layout_root: &mut Flow,
+        layout_root: &mut dyn Flow,
         layout_context: &mut LayoutContext,
         rw_data: &mut LayoutThreadData,
     ) {
         let writing_mode = layout_root.base().writing_mode;
         let (metadata, sender) = (self.profiler_metadata(), self.time_profiler_chan.clone());
         profile(
-            time::ProfilerCategory::LayoutDispListBuild,
+            profile_time::ProfilerCategory::LayoutDispListBuild,
             metadata.clone(),
             sender.clone(),
             || {
@@ -1149,7 +1114,7 @@ impl LayoutThread {
         let mut rw_data = possibly_locked_rw_data.lock();
 
         // Record the time that layout query has been waited.
-        let now = std_time::precise_time_ns();
+        let now = time::precise_time_ns();
         if let ReflowGoal::LayoutQuery(_, timestamp) = data.reflow_goal {
             self.layout_query_waiting_time
                 .increment(now - timestamp)
@@ -1366,7 +1331,7 @@ impl LayoutThread {
         if token.should_traverse() {
             // Recalculate CSS styles and rebuild flows and fragments.
             profile(
-                time::ProfilerCategory::LayoutStyleRecalc,
+                profile_time::ProfilerCategory::LayoutStyleRecalc,
                 self.profiler_metadata(),
                 self.time_profiler_chan.clone(),
                 || {
@@ -1381,8 +1346,8 @@ impl LayoutThread {
             // TODO(pcwalton): Measure energy usage of text shaping, perhaps?
             let text_shaping_time = (font::get_and_reset_text_shaping_performance_counter() as u64) /
                 (self.layout_threads as u64);
-            time::send_profile_data(
-                time::ProfilerCategory::LayoutTextShaping,
+            profile_time::send_profile_data(
+                profile_time::ProfilerCategory::LayoutTextShaping,
                 self.profiler_metadata(),
                 &self.time_profiler_chan,
                 0,
@@ -1447,13 +1412,13 @@ impl LayoutThread {
         reflow_result: &mut ReflowComplete,
     ) {
         let pending_images = match context.pending_images {
-            Some(ref pending) => std_mem::replace(&mut *pending.lock().unwrap(), vec![]),
+            Some(ref pending) => std::mem::replace(&mut *pending.lock().unwrap(), vec![]),
             None => vec![],
         };
         reflow_result.pending_images = pending_images;
 
         let newly_transitioning_nodes = match context.newly_transitioning_nodes {
-            Some(ref nodes) => std_mem::replace(&mut *nodes.lock().unwrap(), vec![]),
+            Some(ref nodes) => std::mem::replace(&mut *nodes.lock().unwrap(), vec![]),
             None => vec![],
         };
         reflow_result.newly_transitioning_nodes = newly_transitioning_nodes;
@@ -1608,7 +1573,7 @@ impl LayoutThread {
                 // Perform an abbreviated style recalc that operates without access to the DOM.
                 let animations = self.running_animations.read();
                 profile(
-                    time::ProfilerCategory::LayoutStyleRecalc,
+                    profile_time::ProfilerCategory::LayoutStyleRecalc,
                     self.profiler_metadata(),
                     self.time_profiler_chan.clone(),
                     || {
@@ -1663,7 +1628,7 @@ impl LayoutThread {
         }
 
         profile(
-            time::ProfilerCategory::LayoutRestyleDamagePropagation,
+            profile_time::ProfilerCategory::LayoutRestyleDamagePropagation,
             self.profiler_metadata(),
             self.time_profiler_chan.clone(),
             || {
@@ -1685,7 +1650,7 @@ impl LayoutThread {
 
         // Resolve generated content.
         profile(
-            time::ProfilerCategory::LayoutGeneratedContent,
+            profile_time::ProfilerCategory::LayoutGeneratedContent,
             self.profiler_metadata(),
             self.time_profiler_chan.clone(),
             || sequential::resolve_generated_content(FlowRef::deref_mut(root_flow), &context),
@@ -1693,7 +1658,7 @@ impl LayoutThread {
 
         // Guess float placement.
         profile(
-            time::ProfilerCategory::LayoutFloatPlacementSpeculation,
+            profile_time::ProfilerCategory::LayoutFloatPlacementSpeculation,
             self.profiler_metadata(),
             self.time_profiler_chan.clone(),
             || sequential::guess_float_placement(FlowRef::deref_mut(root_flow)),
@@ -1707,7 +1672,7 @@ impl LayoutThread {
             .intersects(ServoRestyleDamage::REFLOW | ServoRestyleDamage::REFLOW_OUT_OF_FLOW)
         {
             profile(
-                time::ProfilerCategory::LayoutMain,
+                profile_time::ProfilerCategory::LayoutMain,
                 self.profiler_metadata(),
                 self.time_profiler_chan.clone(),
                 || {
@@ -1733,11 +1698,11 @@ impl LayoutThread {
         }
 
         profile(
-            time::ProfilerCategory::LayoutStoreOverflow,
+            profile_time::ProfilerCategory::LayoutStoreOverflow,
             self.profiler_metadata(),
             self.time_profiler_chan.clone(),
             || {
-                sequential::store_overflow(context, FlowRef::deref_mut(root_flow) as &mut Flow);
+                sequential::store_overflow(context, FlowRef::deref_mut(root_flow) as &mut dyn Flow);
             },
         );
 
@@ -1781,7 +1746,7 @@ impl LayoutThread {
         self.generation.set(self.generation.get() + 1);
     }
 
-    fn reflow_all_nodes(flow: &mut Flow) {
+    fn reflow_all_nodes(flow: &mut dyn Flow) {
         debug!("reflowing all nodes!");
         flow.mut_base().restyle_damage.insert(
             ServoRestyleDamage::REPAINT |
@@ -1828,7 +1793,7 @@ impl ProfilerMetadataFactory for LayoutThread {
 // clearing the frame buffer to white. This ensures that setting a background
 // color on an iframe element, while the iframe content itself has a default
 // transparent background color is handled correctly.
-fn get_root_flow_background_color(flow: &mut Flow) -> webrender_api::ColorF {
+fn get_root_flow_background_color(flow: &mut dyn Flow) -> webrender_api::ColorF {
     let transparent = webrender_api::ColorF {
         r: 0.0,
         g: 0.0,
@@ -1948,7 +1913,7 @@ lazy_static! {
 }
 
 struct RegisteredPainterImpl {
-    painter: Box<Painter>,
+    painter: Box<dyn Painter>,
     name: Atom,
     // FIXME: Should be a PrecomputedHashMap.
     properties: FxHashMap<Atom, PropertyId>,
@@ -1992,17 +1957,17 @@ impl RegisteredPainter for RegisteredPainterImpl {}
 struct RegisteredPaintersImpl(FnvHashMap<Atom, RegisteredPainterImpl>);
 
 impl RegisteredSpeculativePainters for RegisteredPaintersImpl {
-    fn get(&self, name: &Atom) -> Option<&RegisteredSpeculativePainter> {
+    fn get(&self, name: &Atom) -> Option<&dyn RegisteredSpeculativePainter> {
         self.0
             .get(&name)
-            .map(|painter| painter as &RegisteredSpeculativePainter)
+            .map(|painter| painter as &dyn RegisteredSpeculativePainter)
     }
 }
 
 impl RegisteredPainters for RegisteredPaintersImpl {
-    fn get(&self, name: &Atom) -> Option<&RegisteredPainter> {
+    fn get(&self, name: &Atom) -> Option<&dyn RegisteredPainter> {
         self.0
             .get(&name)
-            .map(|painter| painter as &RegisteredPainter)
+            .map(|painter| painter as &dyn RegisteredPainter)
     }
 }
diff --git a/components/layout_traits/lib.rs b/components/layout_traits/lib.rs
index 9fb431c8e2e..0cea8397f7e 100644
--- a/components/layout_traits/lib.rs
+++ b/components/layout_traits/lib.rs
@@ -4,17 +4,6 @@
 
 #![deny(unsafe_code)]
 
-extern crate gfx;
-extern crate ipc_channel;
-extern crate metrics;
-extern crate msg;
-extern crate net_traits;
-extern crate profile_traits;
-extern crate script_traits;
-extern crate servo_channel;
-extern crate servo_url;
-extern crate webrender_api;
-
 // This module contains traits in layout used generically
 //   in the rest of Servo.
 // The traits are here instead of in layout so
@@ -32,6 +21,7 @@ use script_traits::{ConstellationControlMsg, LayoutControlMsg};
 use servo_channel::{Receiver, Sender};
 use servo_url::ServoUrl;
 use std::sync::Arc;
+use webrender_api;
 
 // A static method creating a layout thread
 // Here to remove the compositor -> layout dependency
@@ -46,7 +36,7 @@ pub trait LayoutThreadFactory {
         pipeline_port: IpcReceiver<LayoutControlMsg>,
         constellation_chan: IpcSender<ConstellationMsg>,
         script_chan: IpcSender<ConstellationControlMsg>,
-        image_cache: Arc<ImageCache>,
+        image_cache: Arc<dyn ImageCache>,
         font_cache_thread: FontCacheThread,
         time_profiler_chan: time::ProfilerChan,
         mem_profiler_chan: mem::ProfilerChan,
diff --git a/components/metrics/lib.rs b/components/metrics/lib.rs
index f83a80b9302..e131822b69c 100644
--- a/components/metrics/lib.rs
+++ b/components/metrics/lib.rs
@@ -2,19 +2,10 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate gfx_traits;
-extern crate ipc_channel;
 #[macro_use]
 extern crate log;
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate msg;
-extern crate profile_traits;
-extern crate script_traits;
-extern crate servo_config;
-extern crate servo_url;
-extern crate time;
 
 use gfx_traits::{DisplayList, Epoch};
 use ipc_channel::ipc::IpcSender;
@@ -315,7 +306,7 @@ impl PaintTimeMetrics {
         &self,
         profiler_metadata_factory: &T,
         epoch: Epoch,
-        display_list: &DisplayList,
+        display_list: &dyn DisplayList,
     ) where
         T: ProfilerMetadataFactory,
     {
diff --git a/components/msg/lib.rs b/components/msg/lib.rs
index 3e515e294f8..d2490c142eb 100644
--- a/components/msg/lib.rs
+++ b/components/msg/lib.rs
@@ -10,6 +10,5 @@ extern crate malloc_size_of;
 extern crate malloc_size_of_derive;
 #[macro_use]
 extern crate serde;
-extern crate webrender_api;
 
 pub mod constellation_msg;
diff --git a/components/msg/tests/size_of.rs b/components/msg/tests/size_of.rs
index 62e2647ea61..54995bcb6f7 100644
--- a/components/msg/tests/size_of.rs
+++ b/components/msg/tests/size_of.rs
@@ -4,7 +4,6 @@
 
 #![cfg(target_pointer_width = "64")]
 
-extern crate msg;
 #[macro_use]
 extern crate size_of_test;
 
diff --git a/components/net/Cargo.toml b/components/net/Cargo.toml
index 798c85da1bd..ce05657d371 100644
--- a/components/net/Cargo.toml
+++ b/components/net/Cargo.toml
@@ -1,3 +1,5 @@
+cargo-features = ["rename-dependency"]
+
 [package]
 name = "net"
 version = "0.0.1"
@@ -17,7 +19,7 @@ doctest = false
 base64 = "0.9"
 brotli = "2.5"
 bytes = "0.4"
-cookie = "0.11"
+cookie_rs = {package = "cookie", version = "0.11"}
 devtools_traits = {path = "../devtools_traits"}
 embedder_traits = { path = "../embedder_traits" }
 flate2 = "1"
diff --git a/components/net/connector.rs b/components/net/connector.rs
index 38693e70e24..de9f9b2e087 100644
--- a/components/net/connector.rs
+++ b/components/net/connector.rs
@@ -161,7 +161,7 @@ pub fn create_http_client<E>(
     executor: E,
 ) -> Client<Connector, WrappedBody>
 where
-    E: Executor<Box<Future<Error = (), Item = ()> + Send + 'static>> + Sync + Send + 'static,
+    E: Executor<Box<dyn Future<Error = (), Item = ()> + Send + 'static>> + Sync + Send + 'static,
 {
     let connector =
         HttpsConnector::with_connector(HttpConnector::new(), ssl_connector_builder).unwrap();
diff --git a/components/net/cookie.rs b/components/net/cookie.rs
index 5b9089cc1d3..113a49bd96e 100644
--- a/components/net/cookie.rs
+++ b/components/net/cookie.rs
@@ -5,7 +5,7 @@
 //! Implementation of cookie creation and matching as specified by
 //! http://tools.ietf.org/html/rfc6265
 
-use crate::cookie_rs;
+use cookie_rs;
 use hyper_serde::{self, Serde};
 use net_traits::pub_domains::is_pub_domain;
 use net_traits::CookieSource;
diff --git a/components/net/cookie_storage.rs b/components/net/cookie_storage.rs
index 7eefb164439..2acde56866c 100644
--- a/components/net/cookie_storage.rs
+++ b/components/net/cookie_storage.rs
@@ -5,16 +5,14 @@
 //! Implementation of cookie storage as specified in
 //! http://tools.ietf.org/html/rfc6265
 
+use cookie_rs;
 use crate::cookie::Cookie;
-use crate::cookie_rs;
 use net_traits::pub_domains::reg_suffix;
 use net_traits::CookieSource;
 use servo_url::ServoUrl;
 use std::cmp::Ordering;
 use std::collections::HashMap;
-use time::Tm;
-
-extern crate time;
+use time::{self, Tm};
 
 #[derive(Clone, Debug, Deserialize, Serialize)]
 pub struct CookieStorage {
diff --git a/components/net/fetch/methods.rs b/components/net/fetch/methods.rs
index 0ad92f527ef..499070c04d2 100644
--- a/components/net/fetch/methods.rs
+++ b/components/net/fetch/methods.rs
@@ -41,7 +41,7 @@ lazy_static! {
 
 const FILE_CHUNK_SIZE: usize = 32768; //32 KB
 
-pub type Target<'a> = &'a mut (FetchTaskTarget + Send);
+pub type Target<'a> = &'a mut (dyn FetchTaskTarget + Send);
 
 pub enum Data {
     Payload(Vec<u8>),
diff --git a/components/net/http_loader.rs b/components/net/http_loader.rs
index 8898fdf1924..0bbb64a46cf 100644
--- a/components/net/http_loader.rs
+++ b/components/net/http_loader.rs
@@ -380,7 +380,7 @@ fn obtain_response(
     request_id: Option<&str>,
     is_xhr: bool,
 ) -> Box<
-    Future<
+    dyn Future<
         Item = (
             HyperResponse<WrappedBody>,
             Option<ChromeToDevtoolsControlMsg>,
diff --git a/components/net/lib.rs b/components/net/lib.rs
index e4373edee33..7f36629d306 100644
--- a/components/net/lib.rs
+++ b/components/net/lib.rs
@@ -4,53 +4,18 @@
 
 #![deny(unsafe_code)]
 
-extern crate base64;
-extern crate brotli;
-extern crate bytes;
-extern crate cookie as cookie_rs;
-extern crate devtools_traits;
-extern crate embedder_traits;
-extern crate flate2;
-extern crate headers_core;
-extern crate headers_ext;
-extern crate http;
-extern crate hyper;
-extern crate hyper_openssl;
-extern crate hyper_serde;
-extern crate immeta;
-extern crate ipc_channel;
 #[macro_use]
 extern crate lazy_static;
 #[macro_use]
 extern crate log;
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
 #[macro_use]
-#[no_link]
 extern crate matches;
-extern crate mime;
-extern crate mime_guess;
-extern crate msg;
-extern crate net_traits;
-extern crate openssl;
-extern crate pixels;
 #[macro_use]
 extern crate profile_traits;
 #[macro_use]
 extern crate serde;
-extern crate serde_json;
-extern crate servo_allocator;
-extern crate servo_arc;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_url;
-extern crate time;
-extern crate tokio;
-extern crate url;
-extern crate uuid;
-extern crate webrender_api;
-extern crate ws;
 
 mod blob_loader;
 pub mod connector;
diff --git a/components/net/mime_classifier.rs b/components/net/mime_classifier.rs
index e6716789033..432cb36dee5 100644
--- a/components/net/mime_classifier.rs
+++ b/components/net/mime_classifier.rs
@@ -454,7 +454,7 @@ impl MIMEChecker for BinaryOrPlaintextClassifier {
     }
 }
 struct GroupedClassifier {
-    byte_matchers: Vec<Box<MIMEChecker + Send + Sync>>,
+    byte_matchers: Vec<Box<dyn MIMEChecker + Send + Sync>>,
 }
 impl GroupedClassifier {
     fn image_classifer() -> GroupedClassifier {
diff --git a/components/net/resource_thread.rs b/components/net/resource_thread.rs
index 9793fcb862d..55366efc628 100644
--- a/components/net/resource_thread.rs
+++ b/components/net/resource_thread.rs
@@ -3,9 +3,10 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 //! A thread that takes a URL and streams back the binary data.
+
+use cookie_rs;
 use crate::connector::{create_http_client, create_ssl_connector_builder};
 use crate::cookie;
-use crate::cookie_rs;
 use crate::cookie_storage::CookieStorage;
 use crate::fetch::cors_cache::CorsCache;
 use crate::fetch::methods::{fetch, CancellationListener, FetchContext};
diff --git a/components/net/tests/cookie.rs b/components/net/tests/cookie.rs
index 9cf9aa3ac14..219b2979aa9 100644
--- a/components/net/tests/cookie.rs
+++ b/components/net/tests/cookie.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use crate::cookie_rs;
+use cookie_rs;
 use net::cookie::Cookie;
 use net::cookie_storage::CookieStorage;
 use net_traits::CookieSource;
diff --git a/components/net/tests/http_loader.rs b/components/net/tests/http_loader.rs
index bc5112f1f58..ba8f2e1a3fd 100644
--- a/components/net/tests/http_loader.rs
+++ b/components/net/tests/http_loader.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use crate::cookie_rs::Cookie as CookiePair;
+use cookie_rs::Cookie as CookiePair;
 use crate::fetch;
 use crate::fetch_with_context;
 use crate::make_server;
diff --git a/components/net/tests/main.rs b/components/net/tests/main.rs
index aa7a6aa9cf6..48063adad81 100644
--- a/components/net/tests/main.rs
+++ b/components/net/tests/main.rs
@@ -4,32 +4,8 @@
 
 #![cfg(test)]
 
-extern crate cookie as cookie_rs;
-extern crate devtools_traits;
-extern crate embedder_traits;
-extern crate flate2;
-extern crate futures;
-extern crate headers_core;
-extern crate headers_ext;
-extern crate http;
-extern crate hyper;
-extern crate hyper_serde;
-extern crate ipc_channel;
 #[macro_use]
 extern crate lazy_static;
-extern crate mime;
-extern crate msg;
-extern crate net;
-extern crate net_traits;
-extern crate openssl;
-extern crate profile_traits;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_url;
-extern crate time;
-extern crate tokio;
-extern crate tokio_openssl;
-extern crate url;
 
 mod cookie;
 mod cookie_http_state;
@@ -90,7 +66,7 @@ fn create_embedder_proxy() -> EmbedderProxy {
         }
         impl EventLoopWaker for DummyEventLoopWaker {
             fn wake(&self) {}
-            fn clone(&self) -> Box<EventLoopWaker + Send> {
+            fn clone(&self) -> Box<dyn EventLoopWaker + Send> {
                 Box::new(DummyEventLoopWaker {})
             }
         }
diff --git a/components/net_traits/Cargo.toml b/components/net_traits/Cargo.toml
index e7534bf77ee..6fb2c926dd8 100644
--- a/components/net_traits/Cargo.toml
+++ b/components/net_traits/Cargo.toml
@@ -1,3 +1,5 @@
+cargo-features = ["rename-dependency"]
+
 [package]
 name = "net_traits"
 version = "0.0.1"
@@ -20,7 +22,7 @@ headers-ext = "0.0.3"
 http = "0.1"
 hyper = "0.12"
 hyper_serde = "0.9"
-image = "0.19"
+piston_image = {package = "image", version = "0.19"}
 ipc-channel = "0.11"
 lazy_static = "1"
 log = "0.4"
diff --git a/components/net_traits/image/base.rs b/components/net_traits/image/base.rs
index e1ccf625789..3acd8903006 100644
--- a/components/net_traits/image/base.rs
+++ b/components/net_traits/image/base.rs
@@ -2,8 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use crate::piston_image::{self, DynamicImage, ImageFormat};
 use ipc_channel::ipc::IpcSharedMemory;
+use piston_image::{DynamicImage, ImageFormat};
 use pixels;
 use std::fmt;
 use webrender_api;
diff --git a/components/net_traits/lib.rs b/components/net_traits/lib.rs
index 9acfe5dfcca..b7e11fc4af5 100644
--- a/components/net_traits/lib.rs
+++ b/components/net_traits/lib.rs
@@ -4,15 +4,6 @@
 
 #![deny(unsafe_code)]
 
-extern crate cookie as cookie_rs;
-extern crate embedder_traits;
-extern crate headers_core;
-extern crate headers_ext;
-extern crate http;
-extern crate hyper;
-extern crate hyper_serde;
-extern crate image as piston_image;
-extern crate ipc_channel;
 #[macro_use]
 extern crate lazy_static;
 #[macro_use]
@@ -21,20 +12,12 @@ extern crate log;
 extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate mime;
-extern crate msg;
-extern crate num_traits;
-extern crate pixels;
 #[macro_use]
 extern crate serde;
-extern crate servo_arc;
-extern crate servo_url;
 #[macro_use]
 extern crate url;
-extern crate uuid;
-extern crate webrender_api;
 
-use crate::cookie_rs::Cookie;
+use cookie::Cookie;
 use crate::filemanager_thread::FileManagerThreadMsg;
 use crate::request::{Request, RequestInit};
 use crate::response::{HttpsState, Response, ResponseInit};
diff --git a/components/net_traits/tests/image.rs b/components/net_traits/tests/image.rs
index 238fae97050..e7d2d460d7e 100644
--- a/components/net_traits/tests/image.rs
+++ b/components/net_traits/tests/image.rs
@@ -2,8 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate net_traits;
-
 use net_traits::image::base::detect_image_format;
 
 #[test]
diff --git a/components/net_traits/tests/pub_domains.rs b/components/net_traits/tests/pub_domains.rs
index 307dd2d81dc..c17f8ba8c07 100644
--- a/components/net_traits/tests/pub_domains.rs
+++ b/components/net_traits/tests/pub_domains.rs
@@ -2,8 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate net_traits;
-
 use net_traits::pub_domains::{is_pub_domain, is_reg_domain, pub_suffix, reg_suffix};
 
 // These tests may need to be updated if the PSL changes.
diff --git a/components/net_traits/tests/whitespace.rs b/components/net_traits/tests/whitespace.rs
index 4954e0f67f4..407b060de1b 100644
--- a/components/net_traits/tests/whitespace.rs
+++ b/components/net_traits/tests/whitespace.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate net_traits;
+use net_traits;
 
 #[test]
 fn test_trim_http_whitespace() {
diff --git a/components/pixels/lib.rs b/components/pixels/lib.rs
index 806b854fda2..16c93b7b6af 100644
--- a/components/pixels/lib.rs
+++ b/components/pixels/lib.rs
@@ -2,8 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate euclid;
-
 use euclid::{Point2D, Rect, Size2D};
 use std::borrow::Cow;
 
diff --git a/components/profile/Cargo.toml b/components/profile/Cargo.toml
index d9b3a14aecb..6008c31b10f 100644
--- a/components/profile/Cargo.toml
+++ b/components/profile/Cargo.toml
@@ -1,3 +1,5 @@
+cargo-features = ["rename-dependency"]
+
 [package]
 name = "profile"
 version = "0.0.1"
@@ -11,7 +13,7 @@ name = "profile"
 path = "lib.rs"
 
 [features]
-unstable = ["jemalloc-sys"]
+unstable = ["servo_allocator"]
 
 [dependencies]
 profile_traits = {path = "../profile_traits"}
@@ -22,7 +24,7 @@ log = "0.4"
 serde = "1.0"
 serde_json = "1.0"
 servo_config = {path = "../config"}
-time = "0.1.12"
+time_crate = {package = "time", version = "0.1.12"}
 tokio = "0.1"
 
 [target.'cfg(target_os = "macos")'.dependencies]
@@ -33,4 +35,4 @@ regex = "1.0"
 
 [target.'cfg(not(target_os = "windows"))'.dependencies]
 libc = "0.2"
-jemalloc-sys = {version = "0.1.3", optional = true}
+servo_allocator = {path = "../allocator", optional = true}
diff --git a/components/profile/lib.rs b/components/profile/lib.rs
index 248fd0ab19b..b9c6085be46 100644
--- a/components/profile/lib.rs
+++ b/components/profile/lib.rs
@@ -4,28 +4,12 @@
 
 #![deny(unsafe_code)]
 
-#[allow(unused_extern_crates)]
-extern crate heartbeats_simple;
-extern crate influent;
-extern crate ipc_channel;
-#[cfg(all(feature = "unstable", not(target_os = "windows")))]
-extern crate jemalloc_sys;
-#[cfg(not(target_os = "windows"))]
-extern crate libc;
 #[macro_use]
 extern crate log;
 #[macro_use]
 extern crate profile_traits;
-#[cfg(target_os = "linux")]
-extern crate regex;
 #[macro_use]
 extern crate serde;
-extern crate serde_json;
-extern crate servo_config;
-#[cfg(target_os = "macos")]
-extern crate task_info;
-extern crate time as std_time;
-extern crate tokio;
 
 #[allow(unsafe_code)]
 mod heartbeats;
diff --git a/components/profile/mem.rs b/components/profile/mem.rs
index 8e6a86c59cd..7c60ba07b67 100644
--- a/components/profile/mem.rs
+++ b/components/profile/mem.rs
@@ -496,7 +496,7 @@ mod system_reporter {
     }
 
     #[cfg(all(feature = "unstable", not(target_os = "windows")))]
-    use jemalloc_sys::mallctl;
+    use servo_allocator::jemalloc_sys::mallctl;
 
     #[cfg(all(feature = "unstable", not(target_os = "windows")))]
     fn jemalloc_stat(value_name: &str) -> Option<usize> {
diff --git a/components/profile/time.rs b/components/profile/time.rs
index 7cfdbcee14d..cd78fee4ed6 100644
--- a/components/profile/time.rs
+++ b/components/profile/time.rs
@@ -5,7 +5,6 @@
 //! Timing functions.
 
 use crate::heartbeats;
-use crate::std_time::precise_time_ns;
 use crate::trace_dump::TraceDump;
 use influent::client::{Client, Credentials};
 use influent::create_client;
@@ -26,6 +25,7 @@ use std::io::{self, Write};
 use std::path::Path;
 use std::time::Duration;
 use std::{f64, thread, u32, u64};
+use time_crate::precise_time_ns;
 use tokio;
 use tokio::prelude::Future;
 
diff --git a/components/profile_traits/lib.rs b/components/profile_traits/lib.rs
index 017d35b24c1..cf7034d5962 100644
--- a/components/profile_traits/lib.rs
+++ b/components/profile_traits/lib.rs
@@ -8,15 +8,10 @@
 
 #![deny(unsafe_code)]
 
-extern crate bincode;
-extern crate ipc_channel;
 #[macro_use]
 extern crate log;
 #[macro_use]
 extern crate serde;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate signpost;
 
 #[allow(unsafe_code)]
 pub mod energy;
diff --git a/components/profile_traits/time.rs b/components/profile_traits/time.rs
index 010bb009682..fe819a6cee8 100644
--- a/components/profile_traits/time.rs
+++ b/components/profile_traits/time.rs
@@ -2,13 +2,11 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate time as std_time;
-
-use self::std_time::precise_time_ns;
 use crate::energy::read_energy_uj;
 use ipc_channel::ipc::IpcSender;
 use servo_config::opts;
 use signpost;
+use time::precise_time_ns;
 
 #[derive(Clone, Debug, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
 pub struct TimerMetadata {
diff --git a/components/rand/lib.rs b/components/rand/lib.rs
index 56c20522b76..54c0de6d501 100644
--- a/components/rand/lib.rs
+++ b/components/rand/lib.rs
@@ -16,8 +16,6 @@
 extern crate lazy_static;
 #[macro_use]
 extern crate log;
-extern crate rand;
-extern crate uuid;
 
 #[cfg(target_pointer_width = "64")]
 use rand::isaac::Isaac64Rng as IsaacWordRng;
diff --git a/components/range/lib.rs b/components/range/lib.rs
index 9d65a229717..797ba4b9b83 100644
--- a/components/range/lib.rs
+++ b/components/range/lib.rs
@@ -4,10 +4,8 @@
 
 #![deny(unsafe_code)]
 
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate num_traits;
 #[macro_use]
 extern crate serde;
 
diff --git a/components/remutex/tests/smoke.rs b/components/remutex/tests/smoke.rs
index 743bdfec167..5c095ea703f 100644
--- a/components/remutex/tests/smoke.rs
+++ b/components/remutex/tests/smoke.rs
@@ -10,8 +10,6 @@
 
 // These tests came from https://github.com/rust-lang/rust/blob/master/src/libstd/sys/common/remutex.rs
 
-extern crate servo_remutex;
-
 use servo_remutex::{ReentrantMutex, ReentrantMutexGuard};
 use std::cell::RefCell;
 use std::sync::Arc;
diff --git a/components/script/build.rs b/components/script/build.rs
index 0abb25ef24a..83b96495e16 100644
--- a/components/script/build.rs
+++ b/components/script/build.rs
@@ -2,12 +2,10 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate cmake;
-extern crate phf_codegen;
-extern crate phf_shared;
-extern crate serde_json;
-
-use serde_json::Value;
+use cmake;
+use phf_codegen;
+use phf_shared;
+use serde_json::{self, Value};
 use std::env;
 use std::fmt;
 use std::fs::File;
diff --git a/components/script/dom/abstractworkerglobalscope.rs b/components/script/dom/abstractworkerglobalscope.rs
index ab919bd87c4..e01b98cf944 100644
--- a/components/script/dom/abstractworkerglobalscope.rs
+++ b/components/script/dom/abstractworkerglobalscope.rs
@@ -32,7 +32,7 @@ impl ScriptChan for SendableWorkerScriptChan {
         self.sender.send(msg).map_err(|_| ())
     }
 
-    fn clone(&self) -> Box<ScriptChan + Send> {
+    fn clone(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(SendableWorkerScriptChan {
             sender: self.sender.clone(),
             worker: self.worker.clone(),
@@ -58,7 +58,7 @@ impl ScriptChan for WorkerThreadWorkerChan {
         self.sender.send(msg).map_err(|_| ())
     }
 
-    fn clone(&self) -> Box<ScriptChan + Send> {
+    fn clone(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(WorkerThreadWorkerChan {
             sender: self.sender.clone(),
             worker: self.worker.clone(),
diff --git a/components/script/dom/bindings/root.rs b/components/script/dom/bindings/root.rs
index 25b77e052e6..5318eb11e4d 100644
--- a/components/script/dom/bindings/root.rs
+++ b/components/script/dom/bindings/root.rs
@@ -78,14 +78,14 @@ where
 pub unsafe trait StableTraceObject {
     /// Returns a stable trace object which address won't change for the whole
     /// lifetime of the value.
-    fn stable_trace_object(&self) -> *const JSTraceable;
+    fn stable_trace_object(&self) -> *const dyn JSTraceable;
 }
 
 unsafe impl<T> StableTraceObject for Dom<T>
 where
     T: DomObject,
 {
-    fn stable_trace_object<'a>(&'a self) -> *const JSTraceable {
+    fn stable_trace_object<'a>(&'a self) -> *const dyn JSTraceable {
         // The JSTraceable impl for Reflector doesn't actually do anything,
         // so we need this shenanigan to actually trace the reflector of the
         // T pointer in Dom<T>.
@@ -198,7 +198,7 @@ where
 /// See also [*Exact Stack Rooting - Storing a GCPointer on the CStack*]
 /// (https://developer.mozilla.org/en-US/docs/Mozilla/Projects/SpiderMonkey/Internals/GC/Exact_Stack_Rooting).
 pub struct RootCollection {
-    roots: UnsafeCell<Vec<*const JSTraceable>>,
+    roots: UnsafeCell<Vec<*const dyn JSTraceable>>,
 }
 
 thread_local!(static STACK_ROOTS: Cell<Option<*const RootCollection>> = Cell::new(None));
@@ -228,13 +228,13 @@ impl RootCollection {
     }
 
     /// Starts tracking a trace object.
-    unsafe fn root(&self, object: *const JSTraceable) {
+    unsafe fn root(&self, object: *const dyn JSTraceable) {
         debug_assert!(thread_state::get().is_script());
         (*self.roots.get()).push(object);
     }
 
     /// Stops tracking a trace object, asserting if it isn't found.
-    unsafe fn unroot(&self, object: *const JSTraceable) {
+    unsafe fn unroot(&self, object: *const dyn JSTraceable) {
         debug_assert!(thread_state::get().is_script());
         let roots = &mut *self.roots.get();
         match roots.iter().rposition(|r| *r == object) {
diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index d45bbdef121..d8d3000d037 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -375,7 +375,7 @@ unsafe_no_jsmanaged_fields!(usize, u8, u16, u32, u64);
 unsafe_no_jsmanaged_fields!(isize, i8, i16, i32, i64);
 unsafe_no_jsmanaged_fields!(Error);
 unsafe_no_jsmanaged_fields!(ServoUrl, ImmutableOrigin, MutableOrigin);
-unsafe_no_jsmanaged_fields!(Image, ImageMetadata, ImageCache, PendingImageId);
+unsafe_no_jsmanaged_fields!(Image, ImageMetadata, dyn ImageCache, PendingImageId);
 unsafe_no_jsmanaged_fields!(Metadata);
 unsafe_no_jsmanaged_fields!(NetworkError);
 unsafe_no_jsmanaged_fields!(Atom, Prefix, LocalName, Namespace, QualName);
@@ -461,7 +461,7 @@ unsafe_no_jsmanaged_fields!(AudioBuffer);
 unsafe_no_jsmanaged_fields!(AudioContext<Backend>);
 unsafe_no_jsmanaged_fields!(NodeId);
 unsafe_no_jsmanaged_fields!(AnalysisEngine, DistanceModel, PanningModel, ParamType);
-unsafe_no_jsmanaged_fields!(Player<Error = ServoMediaError>);
+unsafe_no_jsmanaged_fields!(dyn Player<Error = ServoMediaError>);
 unsafe_no_jsmanaged_fields!(Mutex<MediaFrameRenderer>);
 unsafe_no_jsmanaged_fields!(RenderApiSender);
 
@@ -497,7 +497,7 @@ where
 }
 
 // Safe thanks to the Send bound.
-unsafe impl JSTraceable for Box<LayoutRPC + Send + 'static> {
+unsafe impl JSTraceable for Box<dyn LayoutRPC + Send + 'static> {
     #[inline]
     unsafe fn trace(&self, _: *mut JSTracer) {
         // Do nothing
@@ -733,7 +733,7 @@ where
 
 /// Holds a set of JSTraceables that need to be rooted
 struct RootedTraceableSet {
-    set: Vec<*const JSTraceable>,
+    set: Vec<*const dyn JSTraceable>,
 }
 
 thread_local!(/// TLV Holds a set of JSTraceables that need to be rooted
@@ -744,7 +744,7 @@ impl RootedTraceableSet {
         RootedTraceableSet { set: vec![] }
     }
 
-    unsafe fn remove(traceable: *const JSTraceable) {
+    unsafe fn remove(traceable: *const dyn JSTraceable) {
         ROOTED_TRACEABLES.with(|ref traceables| {
             let mut traceables = traceables.borrow_mut();
             let idx = match traceables.set.iter().rposition(|x| *x == traceable) {
@@ -755,7 +755,7 @@ impl RootedTraceableSet {
         });
     }
 
-    unsafe fn add(traceable: *const JSTraceable) {
+    unsafe fn add(traceable: *const dyn JSTraceable) {
         ROOTED_TRACEABLES.with(|ref traceables| {
             traceables.borrow_mut().set.push(traceable);
         })
diff --git a/components/script/dom/bindings/weakref.rs b/components/script/dom/bindings/weakref.rs
index 6e46d0268df..2a9e176af6e 100644
--- a/components/script/dom/bindings/weakref.rs
+++ b/components/script/dom/bindings/weakref.rs
@@ -269,7 +269,7 @@ impl<T: WeakReferenceable> DerefMut for WeakRefVec<T> {
 /// An entry of a vector of weak references. Passed to the closure
 /// given to `WeakRefVec::update`.
 #[allow_unrooted_interior]
-pub struct WeakRefEntry<'a, T: WeakReferenceable + 'a> {
+pub struct WeakRefEntry<'a, T: WeakReferenceable> {
     vec: &'a mut WeakRefVec<T>,
     index: &'a mut usize,
 }
diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index 1bf2a09b50f..6dbd1a860c5 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -126,7 +126,7 @@ impl CanvasRenderingContext2D {
     pub fn new_inherited(
         global: &GlobalScope,
         canvas: Option<&HTMLCanvasElement>,
-        image_cache: Arc<ImageCache>,
+        image_cache: Arc<dyn ImageCache>,
         base_url: ServoUrl,
         size: Size2D<u32>,
     ) -> CanvasRenderingContext2D {
diff --git a/components/script/dom/cssrule.rs b/components/script/dom/cssrule.rs
index 51dc17d3343..65ff5393a89 100644
--- a/components/script/dom/cssrule.rs
+++ b/components/script/dom/cssrule.rs
@@ -44,25 +44,25 @@ impl CSSRule {
         }
     }
 
-    pub fn as_specific(&self) -> &SpecificCSSRule {
+    pub fn as_specific(&self) -> &dyn SpecificCSSRule {
         if let Some(rule) = self.downcast::<CSSStyleRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSFontFaceRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSKeyframesRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSMediaRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSNamespaceRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSViewportRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSKeyframeRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSImportRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else if let Some(rule) = self.downcast::<CSSSupportsRule>() {
-            rule as &SpecificCSSRule
+            rule as &dyn SpecificCSSRule
         } else {
             unreachable!()
         }
diff --git a/components/script/dom/dedicatedworkerglobalscope.rs b/components/script/dom/dedicatedworkerglobalscope.rs
index afe0908c543..f9a3debe9b4 100644
--- a/components/script/dom/dedicatedworkerglobalscope.rs
+++ b/components/script/dom/dedicatedworkerglobalscope.rs
@@ -203,7 +203,7 @@ impl DedicatedWorkerGlobalScope {
         worker_url: ServoUrl,
         from_devtools_receiver: Receiver<DevtoolScriptControlMsg>,
         runtime: Runtime,
-        parent_sender: Box<ScriptChan + Send>,
+        parent_sender: Box<dyn ScriptChan + Send>,
         own_sender: Sender<DedicatedWorkerScriptMsg>,
         receiver: Receiver<DedicatedWorkerScriptMsg>,
         timer_event_chan: IpcSender<TimerEvent>,
@@ -233,7 +233,7 @@ impl DedicatedWorkerGlobalScope {
         worker_url: ServoUrl,
         from_devtools_receiver: Receiver<DevtoolScriptControlMsg>,
         runtime: Runtime,
-        parent_sender: Box<ScriptChan + Send>,
+        parent_sender: Box<dyn ScriptChan + Send>,
         own_sender: Sender<DedicatedWorkerScriptMsg>,
         receiver: Receiver<DedicatedWorkerScriptMsg>,
         timer_event_chan: IpcSender<TimerEvent>,
@@ -263,7 +263,7 @@ impl DedicatedWorkerGlobalScope {
         worker_url: ServoUrl,
         from_devtools_receiver: IpcReceiver<DevtoolScriptControlMsg>,
         worker: TrustedWorkerAddress,
-        parent_sender: Box<ScriptChan + Send>,
+        parent_sender: Box<dyn ScriptChan + Send>,
         own_sender: Sender<DedicatedWorkerScriptMsg>,
         receiver: Receiver<DedicatedWorkerScriptMsg>,
         worker_load_origin: WorkerScriptLoadOrigin,
@@ -396,14 +396,14 @@ impl DedicatedWorkerGlobalScope {
             .expect("Thread spawning failed");
     }
 
-    pub fn script_chan(&self) -> Box<ScriptChan + Send> {
+    pub fn script_chan(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(WorkerThreadWorkerChan {
             sender: self.own_sender.clone(),
             worker: self.worker.borrow().as_ref().unwrap().clone(),
         })
     }
 
-    pub fn new_script_pair(&self) -> (Box<ScriptChan + Send>, Box<ScriptPort + Send>) {
+    pub fn new_script_pair(&self) -> (Box<dyn ScriptChan + Send>, Box<dyn ScriptPort + Send>) {
         let (tx, rx) = channel();
         let chan = Box::new(SendableWorkerScriptChan {
             sender: tx,
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 330a1194d90..4807f892607 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use crate::cookie_rs;
+use cookie::Cookie;
 use crate::document_loader::{DocumentLoader, LoadType};
 use crate::dom::activation::{synthetic_click_activation, ActivationSource};
 use crate::dom::attr::Attr;
@@ -3965,12 +3965,11 @@ impl DocumentMethods for Document {
             return Err(Error::Security);
         }
 
-        let cookies =
-            if let Some(cookie) = cookie_rs::Cookie::parse(cookie.to_string()).ok().map(Serde) {
-                vec![cookie]
-            } else {
-                vec![]
-            };
+        let cookies = if let Some(cookie) = Cookie::parse(cookie.to_string()).ok().map(Serde) {
+            vec![cookie]
+        } else {
+            vec![]
+        };
 
         let _ = self
             .window
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index 8f65f49b7df..38e5b1ae3c0 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -2579,8 +2579,8 @@ impl ElementMethods for Element {
 }
 
 impl VirtualMethods for Element {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<Node>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<Node>() as &dyn VirtualMethods)
     }
 
     fn attribute_affects_presentational_hints(&self, attr: &Attr) -> bool {
@@ -2941,31 +2941,31 @@ impl<'a> SelectorsElement for DomRoot<Element> {
 }
 
 impl Element {
-    pub fn as_maybe_activatable(&self) -> Option<&Activatable> {
+    pub fn as_maybe_activatable(&self) -> Option<&dyn Activatable> {
         let element = match self.upcast::<Node>().type_id() {
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLInputElement,
             )) => {
                 let element = self.downcast::<HTMLInputElement>().unwrap();
-                Some(element as &Activatable)
+                Some(element as &dyn Activatable)
             },
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLButtonElement,
             )) => {
                 let element = self.downcast::<HTMLButtonElement>().unwrap();
-                Some(element as &Activatable)
+                Some(element as &dyn Activatable)
             },
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLAnchorElement,
             )) => {
                 let element = self.downcast::<HTMLAnchorElement>().unwrap();
-                Some(element as &Activatable)
+                Some(element as &dyn Activatable)
             },
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLLabelElement,
             )) => {
                 let element = self.downcast::<HTMLLabelElement>().unwrap();
-                Some(element as &Activatable)
+                Some(element as &dyn Activatable)
             },
             _ => None,
         };
@@ -2978,50 +2978,50 @@ impl Element {
         })
     }
 
-    pub fn as_stylesheet_owner(&self) -> Option<&StylesheetOwner> {
+    pub fn as_stylesheet_owner(&self) -> Option<&dyn StylesheetOwner> {
         if let Some(s) = self.downcast::<HTMLStyleElement>() {
-            return Some(s as &StylesheetOwner);
+            return Some(s as &dyn StylesheetOwner);
         }
 
         if let Some(l) = self.downcast::<HTMLLinkElement>() {
-            return Some(l as &StylesheetOwner);
+            return Some(l as &dyn StylesheetOwner);
         }
 
         None
     }
 
     // https://html.spec.whatwg.org/multipage/#category-submit
-    pub fn as_maybe_validatable(&self) -> Option<&Validatable> {
+    pub fn as_maybe_validatable(&self) -> Option<&dyn Validatable> {
         let element = match self.upcast::<Node>().type_id() {
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLInputElement,
             )) => {
                 let element = self.downcast::<HTMLInputElement>().unwrap();
-                Some(element as &Validatable)
+                Some(element as &dyn Validatable)
             },
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLButtonElement,
             )) => {
                 let element = self.downcast::<HTMLButtonElement>().unwrap();
-                Some(element as &Validatable)
+                Some(element as &dyn Validatable)
             },
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLObjectElement,
             )) => {
                 let element = self.downcast::<HTMLObjectElement>().unwrap();
-                Some(element as &Validatable)
+                Some(element as &dyn Validatable)
             },
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLSelectElement,
             )) => {
                 let element = self.downcast::<HTMLSelectElement>().unwrap();
-                Some(element as &Validatable)
+                Some(element as &dyn Validatable)
             },
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLTextAreaElement,
             )) => {
                 let element = self.downcast::<HTMLTextAreaElement>().unwrap();
-                Some(element as &Validatable)
+                Some(element as &dyn Validatable)
             },
             _ => None,
         };
diff --git a/components/script/dom/eventtarget.rs b/components/script/dom/eventtarget.rs
index 3c1a1dd3381..a9cdbb07ea9 100644
--- a/components/script/dom/eventtarget.rs
+++ b/components/script/dom/eventtarget.rs
@@ -733,7 +733,7 @@ impl EventTargetMethods for EventTarget {
 }
 
 impl VirtualMethods for EventTarget {
-    fn super_type(&self) -> Option<&VirtualMethods> {
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
         None
     }
 }
diff --git a/components/script/dom/globalscope.rs b/components/script/dom/globalscope.rs
index 96d4131f581..4b999d24ec0 100644
--- a/components/script/dom/globalscope.rs
+++ b/components/script/dom/globalscope.rs
@@ -463,7 +463,7 @@ impl GlobalScope {
     }
 
     /// `ScriptChan` to send messages to the event loop of this global scope.
-    pub fn script_chan(&self) -> Box<ScriptChan + Send> {
+    pub fn script_chan(&self) -> Box<dyn ScriptChan + Send> {
         if let Some(window) = self.downcast::<Window>() {
             return MainThreadScriptChan(window.main_thread_script_chan().clone()).clone();
         }
@@ -663,7 +663,7 @@ impl GlobalScope {
     /// Create a new sender/receiver pair that can be used to implement an on-demand
     /// event loop. Used for implementing web APIs that require blocking semantics
     /// without resorting to nested event loops.
-    pub fn new_script_pair(&self) -> (Box<ScriptChan + Send>, Box<ScriptPort + Send>) {
+    pub fn new_script_pair(&self) -> (Box<dyn ScriptChan + Send>, Box<dyn ScriptPort + Send>) {
         if let Some(window) = self.downcast::<Window>() {
             return window.new_script_pair();
         }
diff --git a/components/script/dom/htmlanchorelement.rs b/components/script/dom/htmlanchorelement.rs
index 73f16a8340a..efa96da7e0e 100644
--- a/components/script/dom/htmlanchorelement.rs
+++ b/components/script/dom/htmlanchorelement.rs
@@ -98,8 +98,8 @@ impl HTMLAnchorElement {
 }
 
 impl VirtualMethods for HTMLAnchorElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmlareaelement.rs b/components/script/dom/htmlareaelement.rs
index 1a167bd3b94..45532529808 100644
--- a/components/script/dom/htmlareaelement.rs
+++ b/components/script/dom/htmlareaelement.rs
@@ -285,8 +285,8 @@ impl HTMLAreaElement {
 }
 
 impl VirtualMethods for HTMLAreaElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmlbaseelement.rs b/components/script/dom/htmlbaseelement.rs
index 33ba9886b48..1fe171d5182 100644
--- a/components/script/dom/htmlbaseelement.rs
+++ b/components/script/dom/htmlbaseelement.rs
@@ -108,8 +108,8 @@ impl HTMLBaseElementMethods for HTMLBaseElement {
 }
 
 impl VirtualMethods for HTMLBaseElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlbodyelement.rs b/components/script/dom/htmlbodyelement.rs
index b3bf5e6a76e..fa368f11c12 100644
--- a/components/script/dom/htmlbodyelement.rs
+++ b/components/script/dom/htmlbodyelement.rs
@@ -135,8 +135,8 @@ impl HTMLBodyElementLayoutHelpers for LayoutDom<HTMLBodyElement> {
 }
 
 impl VirtualMethods for HTMLBodyElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_affects_presentational_hints(&self, attr: &Attr) -> bool {
diff --git a/components/script/dom/htmlbuttonelement.rs b/components/script/dom/htmlbuttonelement.rs
index b954c4a7d34..2b58aaea7a0 100755
--- a/components/script/dom/htmlbuttonelement.rs
+++ b/components/script/dom/htmlbuttonelement.rs
@@ -189,8 +189,8 @@ impl HTMLButtonElement {
 }
 
 impl VirtualMethods for HTMLButtonElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 0661f5717f0..2e86193c184 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -407,8 +407,8 @@ impl HTMLCanvasElementMethods for HTMLCanvasElement {
 }
 
 impl VirtualMethods for HTMLCanvasElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlcollection.rs b/components/script/dom/htmlcollection.rs
index 99d3c4775b8..cc2256a6764 100644
--- a/components/script/dom/htmlcollection.rs
+++ b/components/script/dom/htmlcollection.rs
@@ -69,7 +69,10 @@ pub struct HTMLCollection {
 
 impl HTMLCollection {
     #[allow(unrooted_must_root)]
-    pub fn new_inherited(root: &Node, filter: Box<CollectionFilter + 'static>) -> HTMLCollection {
+    pub fn new_inherited(
+        root: &Node,
+        filter: Box<dyn CollectionFilter + 'static>,
+    ) -> HTMLCollection {
         HTMLCollection {
             reflector_: Reflector::new(),
             root: Dom::from_ref(root),
@@ -99,7 +102,7 @@ impl HTMLCollection {
     pub fn new(
         window: &Window,
         root: &Node,
-        filter: Box<CollectionFilter + 'static>,
+        filter: Box<dyn CollectionFilter + 'static>,
     ) -> DomRoot<HTMLCollection> {
         reflect_dom_object(
             Box::new(HTMLCollection::new_inherited(root, filter)),
@@ -111,7 +114,7 @@ impl HTMLCollection {
     pub fn create(
         window: &Window,
         root: &Node,
-        filter: Box<CollectionFilter + 'static>,
+        filter: Box<dyn CollectionFilter + 'static>,
     ) -> DomRoot<HTMLCollection> {
         HTMLCollection::new(window, root, filter)
     }
diff --git a/components/script/dom/htmldetailselement.rs b/components/script/dom/htmldetailselement.rs
index 80d4c1caa98..3f7021dc786 100644
--- a/components/script/dom/htmldetailselement.rs
+++ b/components/script/dom/htmldetailselement.rs
@@ -62,8 +62,8 @@ impl HTMLDetailsElementMethods for HTMLDetailsElement {
 }
 
 impl VirtualMethods for HTMLDetailsElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlelement.rs b/components/script/dom/htmlelement.rs
index c3702a0357a..93b8e099510 100644
--- a/components/script/dom/htmlelement.rs
+++ b/components/script/dom/htmlelement.rs
@@ -718,8 +718,8 @@ impl HTMLElement {
 }
 
 impl VirtualMethods for HTMLElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<Element>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<Element>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlfieldsetelement.rs b/components/script/dom/htmlfieldsetelement.rs
index 2026e7bd5e0..614bed522cd 100644
--- a/components/script/dom/htmlfieldsetelement.rs
+++ b/components/script/dom/htmlfieldsetelement.rs
@@ -95,8 +95,8 @@ impl HTMLFieldSetElementMethods for HTMLFieldSetElement {
 }
 
 impl VirtualMethods for HTMLFieldSetElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlfontelement.rs b/components/script/dom/htmlfontelement.rs
index 0794e4ca432..bf65d411be5 100644
--- a/components/script/dom/htmlfontelement.rs
+++ b/components/script/dom/htmlfontelement.rs
@@ -74,8 +74,8 @@ impl HTMLFontElementMethods for HTMLFontElement {
 }
 
 impl VirtualMethods for HTMLFontElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_affects_presentational_hints(&self, attr: &Attr) -> bool {
diff --git a/components/script/dom/htmlformcontrolscollection.rs b/components/script/dom/htmlformcontrolscollection.rs
index 57261fe26aa..b3a0ef2cede 100644
--- a/components/script/dom/htmlformcontrolscollection.rs
+++ b/components/script/dom/htmlformcontrolscollection.rs
@@ -25,7 +25,7 @@ pub struct HTMLFormControlsCollection {
 impl HTMLFormControlsCollection {
     fn new_inherited(
         root: &Node,
-        filter: Box<CollectionFilter + 'static>,
+        filter: Box<dyn CollectionFilter + 'static>,
     ) -> HTMLFormControlsCollection {
         HTMLFormControlsCollection {
             collection: HTMLCollection::new_inherited(root, filter),
@@ -35,7 +35,7 @@ impl HTMLFormControlsCollection {
     pub fn new(
         window: &Window,
         root: &Node,
-        filter: Box<CollectionFilter + 'static>,
+        filter: Box<dyn CollectionFilter + 'static>,
     ) -> DomRoot<HTMLFormControlsCollection> {
         reflect_dom_object(
             Box::new(HTMLFormControlsCollection::new_inherited(root, filter)),
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index ba322aa20e9..fc9e4832fe5 100755
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -1137,8 +1137,8 @@ pub trait FormControl: DomObject {
 }
 
 impl VirtualMethods for HTMLFormElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
@@ -1175,44 +1175,44 @@ impl VirtualMethods for HTMLFormElement {
 }
 
 pub trait FormControlElementHelpers {
-    fn as_maybe_form_control<'a>(&'a self) -> Option<&'a FormControl>;
+    fn as_maybe_form_control<'a>(&'a self) -> Option<&'a dyn FormControl>;
 }
 
 impl FormControlElementHelpers for Element {
-    fn as_maybe_form_control<'a>(&'a self) -> Option<&'a FormControl> {
+    fn as_maybe_form_control<'a>(&'a self) -> Option<&'a dyn FormControl> {
         let node = self.upcast::<Node>();
 
         match node.type_id() {
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLButtonElement,
-            )) => Some(self.downcast::<HTMLButtonElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLButtonElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLFieldSetElement,
-            )) => Some(self.downcast::<HTMLFieldSetElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLFieldSetElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLImageElement,
-            )) => Some(self.downcast::<HTMLImageElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLImageElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLInputElement,
-            )) => Some(self.downcast::<HTMLInputElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLInputElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLLabelElement,
-            )) => Some(self.downcast::<HTMLLabelElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLLabelElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLLegendElement,
-            )) => Some(self.downcast::<HTMLLegendElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLLegendElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLObjectElement,
-            )) => Some(self.downcast::<HTMLObjectElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLObjectElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLOutputElement,
-            )) => Some(self.downcast::<HTMLOutputElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLOutputElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLSelectElement,
-            )) => Some(self.downcast::<HTMLSelectElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLSelectElement>().unwrap() as &dyn FormControl),
             NodeTypeId::Element(ElementTypeId::HTMLElement(
                 HTMLElementTypeId::HTMLTextAreaElement,
-            )) => Some(self.downcast::<HTMLTextAreaElement>().unwrap() as &FormControl),
+            )) => Some(self.downcast::<HTMLTextAreaElement>().unwrap() as &dyn FormControl),
             _ => None,
         }
     }
diff --git a/components/script/dom/htmlheadelement.rs b/components/script/dom/htmlheadelement.rs
index c3aa6812062..89834cde5fc 100644
--- a/components/script/dom/htmlheadelement.rs
+++ b/components/script/dom/htmlheadelement.rs
@@ -78,8 +78,8 @@ impl HTMLHeadElement {
 }
 
 impl VirtualMethods for HTMLHeadElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
     fn bind_to_tree(&self, tree_in_doc: bool) {
         if let Some(ref s) = self.super_type() {
diff --git a/components/script/dom/htmlhrelement.rs b/components/script/dom/htmlhrelement.rs
index 1abb3727a8b..01b4e4f526c 100644
--- a/components/script/dom/htmlhrelement.rs
+++ b/components/script/dom/htmlhrelement.rs
@@ -95,8 +95,8 @@ impl HTMLHRLayoutHelpers for LayoutDom<HTMLHRElement> {
 }
 
 impl VirtualMethods for HTMLHRElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 83499448cdc..9cae4e83e7a 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -547,8 +547,8 @@ impl HTMLIFrameElementMethods for HTMLIFrameElement {
 }
 
 impl VirtualMethods for HTMLIFrameElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlimageelement.rs b/components/script/dom/htmlimageelement.rs
index 05d1d2804e1..851f9971455 100644
--- a/components/script/dom/htmlimageelement.rs
+++ b/components/script/dom/htmlimageelement.rs
@@ -157,7 +157,7 @@ impl HTMLImageElement {
 /// The context required for asynchronously loading an external image.
 struct ImageContext {
     /// Reference to the script thread image cache.
-    image_cache: Arc<ImageCache>,
+    image_cache: Arc<dyn ImageCache>,
     /// Indicates whether the request failed, and why
     status: Result<(), NetworkError>,
     /// The cache ID for this request.
@@ -229,7 +229,7 @@ impl HTMLImageElement {
     /// Update the current image with a valid URL.
     fn fetch_image(&self, img_url: &ServoUrl) {
         fn add_cache_listener_for_element(
-            image_cache: Arc<ImageCache>,
+            image_cache: Arc<dyn ImageCache>,
             id: PendingImageId,
             elem: &HTMLImageElement,
         ) {
@@ -979,7 +979,7 @@ impl HTMLImageElement {
     fn react_to_environment_changes_sync_steps(&self, generation: u32) {
         // TODO reduce duplicacy of this code
         fn add_cache_listener_for_element(
-            image_cache: Arc<ImageCache>,
+            image_cache: Arc<dyn ImageCache>,
             id: PendingImageId,
             elem: &HTMLImageElement,
             selected_source: String,
@@ -1576,8 +1576,8 @@ impl HTMLImageElementMethods for HTMLImageElement {
 }
 
 impl VirtualMethods for HTMLImageElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn adopting_steps(&self, old_doc: &Document) {
diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index e0f50575a44..051acf352a2 100755
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -1206,8 +1206,8 @@ impl HTMLInputElement {
 }
 
 impl VirtualMethods for HTMLInputElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmllabelelement.rs b/components/script/dom/htmllabelelement.rs
index badc60b5243..7b7129c00ae 100644
--- a/components/script/dom/htmllabelelement.rs
+++ b/components/script/dom/htmllabelelement.rs
@@ -134,8 +134,8 @@ impl HTMLLabelElementMethods for HTMLLabelElement {
 }
 
 impl VirtualMethods for HTMLLabelElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmllegendelement.rs b/components/script/dom/htmllegendelement.rs
index 562c4675a58..345f1a62c55 100644
--- a/components/script/dom/htmllegendelement.rs
+++ b/components/script/dom/htmllegendelement.rs
@@ -52,8 +52,8 @@ impl HTMLLegendElement {
 }
 
 impl VirtualMethods for HTMLLegendElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn bind_to_tree(&self, tree_in_doc: bool) {
diff --git a/components/script/dom/htmllielement.rs b/components/script/dom/htmllielement.rs
index b1b913e86e9..cce6ae1f49e 100644
--- a/components/script/dom/htmllielement.rs
+++ b/components/script/dom/htmllielement.rs
@@ -54,8 +54,8 @@ impl HTMLLIElementMethods for HTMLLIElement {
 }
 
 impl VirtualMethods for HTMLLIElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmllinkelement.rs b/components/script/dom/htmllinkelement.rs
index 74d8e301cff..1efa6924fb8 100644
--- a/components/script/dom/htmllinkelement.rs
+++ b/components/script/dom/htmllinkelement.rs
@@ -177,8 +177,8 @@ fn is_favicon(value: &Option<String>) -> bool {
 }
 
 impl VirtualMethods for HTMLLinkElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index 5182ac1f02d..b178b4b5801 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/components/script/dom/htmlmediaelement.rs
@@ -1351,8 +1351,8 @@ impl HTMLMediaElementMethods for HTMLMediaElement {
 }
 
 impl VirtualMethods for HTMLMediaElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlmetaelement.rs b/components/script/dom/htmlmetaelement.rs
index 7e975c440c9..f6e14f032a3 100644
--- a/components/script/dom/htmlmetaelement.rs
+++ b/components/script/dom/htmlmetaelement.rs
@@ -171,8 +171,8 @@ impl HTMLMetaElementMethods for HTMLMetaElement {
 }
 
 impl VirtualMethods for HTMLMetaElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn bind_to_tree(&self, tree_in_doc: bool) {
diff --git a/components/script/dom/htmlobjectelement.rs b/components/script/dom/htmlobjectelement.rs
index 896c5eb90d1..66076cf5d04 100755
--- a/components/script/dom/htmlobjectelement.rs
+++ b/components/script/dom/htmlobjectelement.rs
@@ -114,8 +114,8 @@ impl Validatable for HTMLObjectElement {
 }
 
 impl VirtualMethods for HTMLObjectElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmloptgroupelement.rs b/components/script/dom/htmloptgroupelement.rs
index 9c6b9e9695f..3a8c6b4fe48 100644
--- a/components/script/dom/htmloptgroupelement.rs
+++ b/components/script/dom/htmloptgroupelement.rs
@@ -63,8 +63,8 @@ impl HTMLOptGroupElementMethods for HTMLOptGroupElement {
 }
 
 impl VirtualMethods for HTMLOptGroupElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmloptionelement.rs b/components/script/dom/htmloptionelement.rs
index a2d9e3609dd..7c17ffe7aa0 100644
--- a/components/script/dom/htmloptionelement.rs
+++ b/components/script/dom/htmloptionelement.rs
@@ -194,8 +194,8 @@ impl HTMLOptionElementMethods for HTMLOptionElement {
 }
 
 impl VirtualMethods for HTMLOptionElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmloptionscollection.rs b/components/script/dom/htmloptionscollection.rs
index 9ad4e7363d0..5c713fe3543 100644
--- a/components/script/dom/htmloptionscollection.rs
+++ b/components/script/dom/htmloptionscollection.rs
@@ -32,7 +32,7 @@ pub struct HTMLOptionsCollection {
 impl HTMLOptionsCollection {
     fn new_inherited(
         select: &HTMLSelectElement,
-        filter: Box<CollectionFilter + 'static>,
+        filter: Box<dyn CollectionFilter + 'static>,
     ) -> HTMLOptionsCollection {
         HTMLOptionsCollection {
             collection: HTMLCollection::new_inherited(select.upcast(), filter),
@@ -42,7 +42,7 @@ impl HTMLOptionsCollection {
     pub fn new(
         window: &Window,
         select: &HTMLSelectElement,
-        filter: Box<CollectionFilter + 'static>,
+        filter: Box<dyn CollectionFilter + 'static>,
     ) -> DomRoot<HTMLOptionsCollection> {
         reflect_dom_object(
             Box::new(HTMLOptionsCollection::new_inherited(select, filter)),
diff --git a/components/script/dom/htmloutputelement.rs b/components/script/dom/htmloutputelement.rs
index 1ca4cabba25..54ea702608c 100644
--- a/components/script/dom/htmloutputelement.rs
+++ b/components/script/dom/htmloutputelement.rs
@@ -71,8 +71,8 @@ impl HTMLOutputElementMethods for HTMLOutputElement {
 }
 
 impl VirtualMethods for HTMLOutputElement {
-    fn super_type<'b>(&'b self) -> Option<&'b VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type<'b>(&'b self) -> Option<&'b dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlscriptelement.rs b/components/script/dom/htmlscriptelement.rs
index 1cc66221848..47a4950b3d6 100644
--- a/components/script/dom/htmlscriptelement.rs
+++ b/components/script/dom/htmlscriptelement.rs
@@ -708,8 +708,8 @@ impl HTMLScriptElement {
 }
 
 impl VirtualMethods for HTMLScriptElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlselectelement.rs b/components/script/dom/htmlselectelement.rs
index aa8abc4feb2..c91b483e2d8 100755
--- a/components/script/dom/htmlselectelement.rs
+++ b/components/script/dom/htmlselectelement.rs
@@ -354,8 +354,8 @@ impl HTMLSelectElementMethods for HTMLSelectElement {
 }
 
 impl VirtualMethods for HTMLSelectElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlsourceelement.rs b/components/script/dom/htmlsourceelement.rs
index 4cdbba9f620..3defc6b235f 100644
--- a/components/script/dom/htmlsourceelement.rs
+++ b/components/script/dom/htmlsourceelement.rs
@@ -63,8 +63,8 @@ impl HTMLSourceElement {
 }
 
 impl VirtualMethods for HTMLSourceElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmlstyleelement.rs b/components/script/dom/htmlstyleelement.rs
index ede2cb743a8..364640fa169 100644
--- a/components/script/dom/htmlstyleelement.rs
+++ b/components/script/dom/htmlstyleelement.rs
@@ -169,8 +169,8 @@ impl HTMLStyleElement {
 }
 
 impl VirtualMethods for HTMLStyleElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn children_changed(&self, mutation: &ChildrenMutation) {
diff --git a/components/script/dom/htmltablecellelement.rs b/components/script/dom/htmltablecellelement.rs
index ddf668bb4d4..f9ef8724b71 100644
--- a/components/script/dom/htmltablecellelement.rs
+++ b/components/script/dom/htmltablecellelement.rs
@@ -145,8 +145,8 @@ impl HTMLTableCellElementLayoutHelpers for LayoutDom<HTMLTableCellElement> {
 }
 
 impl VirtualMethods for HTMLTableCellElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, local_name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmltableelement.rs b/components/script/dom/htmltableelement.rs
index d921855ae66..5283d6a9361 100644
--- a/components/script/dom/htmltableelement.rs
+++ b/components/script/dom/htmltableelement.rs
@@ -447,8 +447,8 @@ impl HTMLTableElementLayoutHelpers for LayoutDom<HTMLTableElement> {
 }
 
 impl VirtualMethods for HTMLTableElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmltablerowelement.rs b/components/script/dom/htmltablerowelement.rs
index 5255fdc0b0c..044e52f2389 100644
--- a/components/script/dom/htmltablerowelement.rs
+++ b/components/script/dom/htmltablerowelement.rs
@@ -165,8 +165,8 @@ impl HTMLTableRowElementLayoutHelpers for LayoutDom<HTMLTableRowElement> {
 }
 
 impl VirtualMethods for HTMLTableRowElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, local_name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmltablesectionelement.rs b/components/script/dom/htmltablesectionelement.rs
index f1422589c27..f12ed26ffc8 100644
--- a/components/script/dom/htmltablesectionelement.rs
+++ b/components/script/dom/htmltablesectionelement.rs
@@ -102,8 +102,8 @@ impl HTMLTableSectionElementLayoutHelpers for LayoutDom<HTMLTableSectionElement>
 }
 
 impl VirtualMethods for HTMLTableSectionElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn parse_plain_attribute(&self, local_name: &LocalName, value: DOMString) -> AttrValue {
diff --git a/components/script/dom/htmltemplateelement.rs b/components/script/dom/htmltemplateelement.rs
index a080373af2c..7689e1efdc1 100644
--- a/components/script/dom/htmltemplateelement.rs
+++ b/components/script/dom/htmltemplateelement.rs
@@ -64,8 +64,8 @@ impl HTMLTemplateElementMethods for HTMLTemplateElement {
 }
 
 impl VirtualMethods for HTMLTemplateElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     /// <https://html.spec.whatwg.org/multipage/#template-adopting-steps>
diff --git a/components/script/dom/htmltextareaelement.rs b/components/script/dom/htmltextareaelement.rs
index 05023ab683b..89ffff3e030 100755
--- a/components/script/dom/htmltextareaelement.rs
+++ b/components/script/dom/htmltextareaelement.rs
@@ -386,8 +386,8 @@ impl HTMLTextAreaElement {
 }
 
 impl VirtualMethods for HTMLTextAreaElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/htmltitleelement.rs b/components/script/dom/htmltitleelement.rs
index da4414d9a91..9fdd1663ed6 100644
--- a/components/script/dom/htmltitleelement.rs
+++ b/components/script/dom/htmltitleelement.rs
@@ -60,8 +60,8 @@ impl HTMLTitleElementMethods for HTMLTitleElement {
 }
 
 impl VirtualMethods for HTMLTitleElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
     }
 
     fn children_changed(&self, mutation: &ChildrenMutation) {
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 2c637f78a98..6854dd9d9cf 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -2616,8 +2616,8 @@ pub fn window_from_node<T: DerivedFrom<Node> + DomObject>(derived: &T) -> DomRoo
 }
 
 impl VirtualMethods for Node {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<EventTarget>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<EventTarget>() as &dyn VirtualMethods)
     }
 
     fn children_changed(&self, mutation: &ChildrenMutation) {
diff --git a/components/script/dom/paintworkletglobalscope.rs b/components/script/dom/paintworkletglobalscope.rs
index 91ceedaa576..6a9a517298f 100644
--- a/components/script/dom/paintworkletglobalscope.rs
+++ b/components/script/dom/paintworkletglobalscope.rs
@@ -131,7 +131,7 @@ impl PaintWorkletGlobalScope {
         unsafe { PaintWorkletGlobalScopeBinding::Wrap(runtime.cx(), global) }
     }
 
-    pub fn image_cache(&self) -> Arc<ImageCache> {
+    pub fn image_cache(&self) -> Arc<dyn ImageCache> {
         self.image_cache.clone()
     }
 
@@ -396,7 +396,7 @@ impl PaintWorkletGlobalScope {
         }
     }
 
-    fn painter(&self, name: Atom) -> Box<Painter> {
+    fn painter(&self, name: Atom) -> Box<dyn Painter> {
         // Rather annoyingly we have to use a mutex here to make the painter Sync.
         struct WorkletPainter {
             name: Atom,
diff --git a/components/script/dom/promisenativehandler.rs b/components/script/dom/promisenativehandler.rs
index 8358de2f49e..f9c2dba5f66 100644
--- a/components/script/dom/promisenativehandler.rs
+++ b/components/script/dom/promisenativehandler.rs
@@ -26,8 +26,8 @@ pub struct PromiseNativeHandler {
 impl PromiseNativeHandler {
     pub fn new(
         global: &GlobalScope,
-        resolve: Option<Box<Callback>>,
-        reject: Option<Box<Callback>>,
+        resolve: Option<Box<dyn Callback>>,
+        reject: Option<Box<dyn Callback>>,
     ) -> DomRoot<PromiseNativeHandler> {
         reflect_dom_object(
             Box::new(PromiseNativeHandler {
@@ -40,7 +40,7 @@ impl PromiseNativeHandler {
         )
     }
 
-    fn callback(callback: &Option<Box<Callback>>, cx: *mut JSContext, v: HandleValue) {
+    fn callback(callback: &Option<Box<dyn Callback>>, cx: *mut JSContext, v: HandleValue) {
         if let Some(ref callback) = *callback {
             callback.callback(cx, v)
         }
diff --git a/components/script/dom/serviceworkerglobalscope.rs b/components/script/dom/serviceworkerglobalscope.rs
index 06f11adaad8..c6f87f6e144 100644
--- a/components/script/dom/serviceworkerglobalscope.rs
+++ b/components/script/dom/serviceworkerglobalscope.rs
@@ -116,7 +116,7 @@ impl ScriptChan for ServiceWorkerChan {
             .map_err(|_| ())
     }
 
-    fn clone(&self) -> Box<ScriptChan + Send> {
+    fn clone(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(ServiceWorkerChan {
             sender: self.sender.clone(),
         })
@@ -412,7 +412,7 @@ impl ServiceWorkerGlobalScope {
         }
     }
 
-    pub fn script_chan(&self) -> Box<ScriptChan + Send> {
+    pub fn script_chan(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(ServiceWorkerChan {
             sender: self.own_sender.clone(),
         })
diff --git a/components/script/dom/svgelement.rs b/components/script/dom/svgelement.rs
index 39dbbf3b161..df138778166 100644
--- a/components/script/dom/svgelement.rs
+++ b/components/script/dom/svgelement.rs
@@ -29,7 +29,7 @@ impl SVGElement {
 }
 
 impl VirtualMethods for SVGElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<Element>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<Element>() as &dyn VirtualMethods)
     }
 }
diff --git a/components/script/dom/svggraphicselement.rs b/components/script/dom/svggraphicselement.rs
index 713efced553..b0a6590027b 100644
--- a/components/script/dom/svggraphicselement.rs
+++ b/components/script/dom/svggraphicselement.rs
@@ -42,7 +42,7 @@ impl SVGGraphicsElement {
 }
 
 impl VirtualMethods for SVGGraphicsElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<SVGElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<SVGElement>() as &dyn VirtualMethods)
     }
 }
diff --git a/components/script/dom/svgsvgelement.rs b/components/script/dom/svgsvgelement.rs
index 60c90544aca..6ea48c344e6 100644
--- a/components/script/dom/svgsvgelement.rs
+++ b/components/script/dom/svgsvgelement.rs
@@ -75,8 +75,8 @@ impl LayoutSVGSVGElementHelpers for LayoutDom<SVGSVGElement> {
 }
 
 impl VirtualMethods for SVGSVGElement {
-    fn super_type(&self) -> Option<&VirtualMethods> {
-        Some(self.upcast::<SVGGraphicsElement>() as &VirtualMethods)
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<SVGGraphicsElement>() as &dyn VirtualMethods)
     }
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
diff --git a/components/script/dom/testbinding.rs b/components/script/dom/testbinding.rs
index e0f9af46b3b..b8baddb46ae 100644
--- a/components/script/dom/testbinding.rs
+++ b/components/script/dom/testbinding.rs
@@ -1028,7 +1028,7 @@ impl TestBindingMethods for TestBinding {
             handler: Rc<SimpleCallback>,
         }
         impl SimpleHandler {
-            fn new(callback: Rc<SimpleCallback>) -> Box<Callback> {
+            fn new(callback: Rc<SimpleCallback>) -> Box<dyn Callback> {
                 Box::new(SimpleHandler { handler: callback })
             }
         }
diff --git a/components/script/dom/virtualmethods.rs b/components/script/dom/virtualmethods.rs
index 3e28f02587d..7e0f5ce28c9 100644
--- a/components/script/dom/virtualmethods.rs
+++ b/components/script/dom/virtualmethods.rs
@@ -59,7 +59,7 @@ use style::attr::AttrValue;
 pub trait VirtualMethods {
     /// Returns self as the superclass of the implementation for this trait,
     /// if any.
-    fn super_type(&self) -> Option<&VirtualMethods>;
+    fn super_type(&self) -> Option<&dyn VirtualMethods>;
 
     /// Called when attributes of a node are mutated.
     /// <https://dom.spec.whatwg.org/#attribute-is-set>
@@ -152,120 +152,120 @@ pub trait VirtualMethods {
 /// method call on the trait object will invoke the corresponding method on the
 /// concrete type, propagating up the parent hierarchy unless otherwise
 /// interrupted.
-pub fn vtable_for(node: &Node) -> &VirtualMethods {
+pub fn vtable_for(node: &Node) -> &dyn VirtualMethods {
     match node.type_id() {
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLAnchorElement)) => {
-            node.downcast::<HTMLAnchorElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLAnchorElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLAreaElement)) => {
-            node.downcast::<HTMLAreaElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLAreaElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLBaseElement)) => {
-            node.downcast::<HTMLBaseElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLBaseElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLBodyElement)) => {
-            node.downcast::<HTMLBodyElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLBodyElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLButtonElement)) => {
-            node.downcast::<HTMLButtonElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLButtonElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLCanvasElement)) => {
-            node.downcast::<HTMLCanvasElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLCanvasElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLDetailsElement)) => {
-            node.downcast::<HTMLDetailsElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLDetailsElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLFieldSetElement)) => {
-            node.downcast::<HTMLFieldSetElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLFieldSetElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLFontElement)) => {
-            node.downcast::<HTMLFontElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLFontElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLFormElement)) => {
-            node.downcast::<HTMLFormElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLFormElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLHeadElement)) => {
-            node.downcast::<HTMLHeadElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLHeadElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLHRElement)) => {
-            node.downcast::<HTMLHRElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLHRElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLImageElement)) => {
-            node.downcast::<HTMLImageElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLImageElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLIFrameElement)) => {
-            node.downcast::<HTMLIFrameElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLIFrameElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLInputElement)) => {
-            node.downcast::<HTMLInputElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLInputElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLLabelElement)) => {
-            node.downcast::<HTMLLabelElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLLabelElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLLIElement)) => {
-            node.downcast::<HTMLLIElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLLIElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLLinkElement)) => {
-            node.downcast::<HTMLLinkElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLLinkElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLMediaElement(_))) => {
-            node.downcast::<HTMLMediaElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLMediaElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLMetaElement)) => {
-            node.downcast::<HTMLMetaElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLMetaElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLObjectElement)) => {
-            node.downcast::<HTMLObjectElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLObjectElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLOptGroupElement)) => {
-            node.downcast::<HTMLOptGroupElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLOptGroupElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLOptionElement)) => {
-            node.downcast::<HTMLOptionElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLOptionElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLOutputElement)) => {
-            node.downcast::<HTMLOutputElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLOutputElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLScriptElement)) => {
-            node.downcast::<HTMLScriptElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLScriptElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLSelectElement)) => {
-            node.downcast::<HTMLSelectElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLSelectElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLSourceElement)) => {
-            node.downcast::<HTMLSourceElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLSourceElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLStyleElement)) => {
-            node.downcast::<HTMLStyleElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLStyleElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLTableElement)) => {
-            node.downcast::<HTMLTableElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLTableElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(
             HTMLElementTypeId::HTMLTableCellElement,
-        )) => node.downcast::<HTMLTableCellElement>().unwrap() as &VirtualMethods,
+        )) => node.downcast::<HTMLTableCellElement>().unwrap() as &dyn VirtualMethods,
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLTableRowElement)) => {
-            node.downcast::<HTMLTableRowElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLTableRowElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(
             HTMLElementTypeId::HTMLTableSectionElement,
-        )) => node.downcast::<HTMLTableSectionElement>().unwrap() as &VirtualMethods,
+        )) => node.downcast::<HTMLTableSectionElement>().unwrap() as &dyn VirtualMethods,
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLTemplateElement)) => {
-            node.downcast::<HTMLTemplateElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLTemplateElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLTextAreaElement)) => {
-            node.downcast::<HTMLTextAreaElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLTextAreaElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLTitleElement)) => {
-            node.downcast::<HTMLTitleElement>().unwrap() as &VirtualMethods
+            node.downcast::<HTMLTitleElement>().unwrap() as &dyn VirtualMethods
         },
         NodeTypeId::Element(ElementTypeId::SVGElement(SVGElementTypeId::SVGGraphicsElement(
             SVGGraphicsElementTypeId::SVGSVGElement,
-        ))) => node.downcast::<SVGSVGElement>().unwrap() as &VirtualMethods,
+        ))) => node.downcast::<SVGSVGElement>().unwrap() as &dyn VirtualMethods,
         NodeTypeId::Element(ElementTypeId::Element) => {
-            node.downcast::<Element>().unwrap() as &VirtualMethods
+            node.downcast::<Element>().unwrap() as &dyn VirtualMethods
         },
-        NodeTypeId::Element(_) => node.downcast::<HTMLElement>().unwrap() as &VirtualMethods,
-        _ => node as &VirtualMethods,
+        NodeTypeId::Element(_) => node.downcast::<HTMLElement>().unwrap() as &dyn VirtualMethods,
+        _ => node as &dyn VirtualMethods,
     }
 }
diff --git a/components/script/dom/webgl_extensions/extensions.rs b/components/script/dom/webgl_extensions/extensions.rs
index 76c995068dc..8b91e0cbd07 100644
--- a/components/script/dom/webgl_extensions/extensions.rs
+++ b/components/script/dom/webgl_extensions/extensions.rs
@@ -139,7 +139,7 @@ impl WebGLExtensionFeatures {
 #[must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 pub struct WebGLExtensions {
-    extensions: DomRefCell<HashMap<String, Box<WebGLExtensionWrapper>>>,
+    extensions: DomRefCell<HashMap<String, Box<dyn WebGLExtensionWrapper>>>,
     features: DomRefCell<WebGLExtensionFeatures>,
     webgl_version: WebGLVersion,
 }
diff --git a/components/script/dom/webgl_extensions/wrapper.rs b/components/script/dom/webgl_extensions/wrapper.rs
index 9918952dc73..11c9bac3d7e 100644
--- a/components/script/dom/webgl_extensions/wrapper.rs
+++ b/components/script/dom/webgl_extensions/wrapper.rs
@@ -25,7 +25,7 @@ pub trait WebGLExtensionWrapper: JSTraceable + MallocSizeOf {
     fn is_enabled(&self) -> bool;
     fn enable(&self, ext: &WebGLExtensions);
     fn name(&self) -> &'static str;
-    fn as_any(&self) -> &Any;
+    fn as_any(&self) -> &dyn Any;
 }
 
 #[must_root]
@@ -85,7 +85,7 @@ where
         T::name()
     }
 
-    fn as_any<'a>(&'a self) -> &'a Any {
+    fn as_any<'a>(&'a self) -> &'a dyn Any {
         self
     }
 }
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index c9ec7317a3c..9723395d0fa 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -384,7 +384,7 @@ impl Window {
         self.networking_task_source.clone()
     }
 
-    pub fn history_traversal_task_source(&self) -> Box<ScriptChan + Send> {
+    pub fn history_traversal_task_source(&self) -> Box<dyn ScriptChan + Send> {
         self.history_traversal_task_source.clone()
     }
 
@@ -412,12 +412,12 @@ impl Window {
         self.parent_info
     }
 
-    pub fn new_script_pair(&self) -> (Box<ScriptChan + Send>, Box<ScriptPort + Send>) {
+    pub fn new_script_pair(&self) -> (Box<dyn ScriptChan + Send>, Box<dyn ScriptPort + Send>) {
         let (tx, rx) = channel();
         (Box::new(SendableMainThreadScriptChan(tx)), Box::new(rx))
     }
 
-    pub fn image_cache(&self) -> Arc<ImageCache> {
+    pub fn image_cache(&self) -> Arc<dyn ImageCache> {
         self.image_cache.clone()
     }
 
@@ -446,7 +446,7 @@ impl Window {
         &self.bluetooth_extra_permission_data
     }
 
-    pub fn css_error_reporter(&self) -> Option<&ParseErrorReporter> {
+    pub fn css_error_reporter(&self) -> Option<&dyn ParseErrorReporter> {
         Some(&self.error_reporter)
     }
 
@@ -1641,7 +1641,7 @@ impl Window {
         )
     }
 
-    pub fn layout(&self) -> &LayoutRPC {
+    pub fn layout(&self) -> &dyn LayoutRPC {
         &*self.layout_rpc
     }
 
@@ -2089,7 +2089,7 @@ impl Window {
         remote_event_task_source: RemoteEventTaskSource,
         websocket_task_source: WebsocketTaskSource,
         image_cache_chan: Sender<ImageCacheMsg>,
-        image_cache: Arc<ImageCache>,
+        image_cache: Arc<dyn ImageCache>,
         resource_threads: ResourceThreads,
         bluetooth_thread: IpcSender<BluetoothRequest>,
         mem_profiler_chan: MemProfilerChan,
@@ -2112,7 +2112,7 @@ impl Window {
         webrender_document: DocumentId,
         webrender_api_sender: RenderApiSender,
     ) -> DomRoot<Self> {
-        let layout_rpc: Box<LayoutRPC + Send> = {
+        let layout_rpc: Box<dyn LayoutRPC + Send> = {
             let (rpc_send, rpc_recv) = channel();
             layout_chan.send(Msg::GetRPC(rpc_send)).unwrap();
             rpc_recv.recv().unwrap()
diff --git a/components/script/dom/workerglobalscope.rs b/components/script/dom/workerglobalscope.rs
index a9b1fc4aca4..015c18f2644 100644
--- a/components/script/dom/workerglobalscope.rs
+++ b/components/script/dom/workerglobalscope.rs
@@ -408,7 +408,7 @@ impl WorkerGlobalScope {
         }
     }
 
-    pub fn script_chan(&self) -> Box<ScriptChan + Send> {
+    pub fn script_chan(&self) -> Box<dyn ScriptChan + Send> {
         let dedicated = self.downcast::<DedicatedWorkerGlobalScope>();
         let service_worker = self.downcast::<ServiceWorkerGlobalScope>();
         if let Some(dedicated) = dedicated {
@@ -444,7 +444,7 @@ impl WorkerGlobalScope {
         WebsocketTaskSource(self.script_chan(), self.pipeline_id())
     }
 
-    pub fn new_script_pair(&self) -> (Box<ScriptChan + Send>, Box<ScriptPort + Send>) {
+    pub fn new_script_pair(&self) -> (Box<dyn ScriptChan + Send>, Box<dyn ScriptPort + Send>) {
         let dedicated = self.downcast::<DedicatedWorkerGlobalScope>();
         if let Some(dedicated) = dedicated {
             return dedicated.new_script_pair();
diff --git a/components/script/dom/workletglobalscope.rs b/components/script/dom/workletglobalscope.rs
index 9e672723c54..3d971390614 100644
--- a/components/script/dom/workletglobalscope.rs
+++ b/components/script/dom/workletglobalscope.rs
@@ -93,7 +93,12 @@ impl WorkletGlobalScope {
     }
 
     /// Register a paint worklet to the script thread.
-    pub fn register_paint_worklet(&self, name: Atom, properties: Vec<Atom>, painter: Box<Painter>) {
+    pub fn register_paint_worklet(
+        &self,
+        name: Atom,
+        properties: Vec<Atom>,
+        painter: Box<dyn Painter>,
+    ) {
         self.to_script_thread_sender
             .send(MainThreadScriptMsg::RegisterPaintWorklet {
                 pipeline_id: self.globalscope.pipeline_id(),
@@ -147,7 +152,7 @@ pub struct WorkletGlobalScopeInit {
     /// Message to send to the scheduler
     pub scheduler_chan: IpcSender<TimerSchedulerMsg>,
     /// The image cache
-    pub image_cache: Arc<ImageCache>,
+    pub image_cache: Arc<dyn ImageCache>,
 }
 
 /// <https://drafts.css-houdini.org/worklets/#worklet-global-scope-type>
diff --git a/components/script/layout_image.rs b/components/script/layout_image.rs
index 99240074eaa..68a3e788cf4 100644
--- a/components/script/layout_image.rs
+++ b/components/script/layout_image.rs
@@ -21,7 +21,7 @@ use std::sync::{Arc, Mutex};
 
 struct LayoutImageContext {
     id: PendingImageId,
-    cache: Arc<ImageCache>,
+    cache: Arc<dyn ImageCache>,
 }
 
 impl FetchResponseListener for LayoutImageContext {
@@ -49,7 +49,7 @@ pub fn fetch_image_for_layout(
     url: ServoUrl,
     node: &Node,
     id: PendingImageId,
-    cache: Arc<ImageCache>,
+    cache: Arc<dyn ImageCache>,
 ) {
     let context = Arc::new(Mutex::new(LayoutImageContext {
         id: id,
diff --git a/components/script/lib.rs b/components/script/lib.rs
index 1eb70033d32..1e4579597a6 100644
--- a/components/script/lib.rs
+++ b/components/script/lib.rs
@@ -17,105 +17,38 @@
     allow(unknown_lints)
 )]
 
-extern crate app_units;
-#[cfg(any(feature = "webgl_backtrace", feature = "js_backtrace"))]
-extern crate backtrace;
-extern crate base64;
 #[macro_use]
 extern crate bitflags;
-extern crate bluetooth_traits;
-extern crate byteorder;
-extern crate canvas_traits;
-extern crate caseless;
-extern crate chrono;
-extern crate cookie as cookie_rs;
 #[macro_use]
 extern crate cssparser;
 #[macro_use]
 extern crate deny_public_fields;
-extern crate devtools_traits;
-extern crate dom_struct;
 #[macro_use]
 extern crate domobject_derive;
-extern crate embedder_traits;
-extern crate encoding_rs;
 #[macro_use]
 extern crate enum_iterator;
-extern crate euclid;
-extern crate fnv;
-extern crate gleam;
-extern crate half;
-extern crate headers_core;
-extern crate headers_ext;
 #[macro_use]
 extern crate html5ever;
-extern crate http;
-extern crate hyper;
-extern crate hyper_serde;
-extern crate image;
-extern crate ipc_channel;
 #[macro_use]
 extern crate js;
 #[macro_use]
 extern crate jstraceable_derive;
-extern crate keyboard_types;
 #[macro_use]
 extern crate lazy_static;
-extern crate libc;
 #[macro_use]
 extern crate log;
 #[macro_use]
 extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate metrics;
-extern crate mime;
-extern crate mime_guess;
-extern crate mitochondria;
-extern crate mozangle;
-extern crate msg;
-extern crate net_traits;
-extern crate num_traits;
-extern crate offscreen_gl_context;
-extern crate parking_lot;
-extern crate phf;
-extern crate pixels;
 #[macro_use]
 extern crate profile_traits;
-extern crate ref_filter_map;
-extern crate ref_slice;
-extern crate regex;
-extern crate script_layout_interface;
-extern crate script_traits;
-extern crate selectors;
-extern crate serde;
-extern crate serde_bytes;
-extern crate servo_allocator;
-extern crate servo_arc;
 #[macro_use]
 extern crate servo_atoms;
 #[macro_use]
 extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_geometry;
-extern crate servo_media;
-extern crate servo_rand;
-extern crate servo_url;
-extern crate smallvec;
 #[macro_use]
 extern crate style;
-extern crate style_traits;
-extern crate swapper;
-extern crate time;
-#[cfg(target_os = "linux")]
-extern crate tinyfiledialogs;
-extern crate unicode_segmentation;
-extern crate url;
-extern crate utf8;
-extern crate uuid;
-extern crate webrender_api;
-extern crate webvr_traits;
-extern crate xml5ever;
 
 #[macro_use]
 mod task;
diff --git a/components/script/script_runtime.rs b/components/script/script_runtime.rs
index 8647c48d1ce..f0cdd8ccad0 100644
--- a/components/script/script_runtime.rs
+++ b/components/script/script_runtime.rs
@@ -66,7 +66,7 @@ pub enum CommonScriptMsg {
     /// Generic message that encapsulates event handling.
     Task(
         ScriptThreadEventCategory,
-        Box<TaskBox>,
+        Box<dyn TaskBox>,
         Option<PipelineId>,
         TaskSourceName,
     ),
@@ -88,7 +88,7 @@ pub trait ScriptChan: JSTraceable {
     /// Send a message to the associated event loop.
     fn send(&self, msg: CommonScriptMsg) -> Result<(), ()>;
     /// Clone this handle.
-    fn clone(&self) -> Box<ScriptChan + Send>;
+    fn clone(&self) -> Box<dyn ScriptChan + Send>;
 }
 
 #[derive(Clone, Copy, Debug, Eq, Hash, JSTraceable, PartialEq)]
@@ -539,7 +539,7 @@ unsafe extern "C" fn get_size(obj: *mut JSObject) -> usize {
             if dom_object.is_null() {
                 return 0;
             }
-            let mut ops = MallocSizeOfOps::new(::servo_allocator::usable_size, None, None);
+            let mut ops = MallocSizeOfOps::new(servo_allocator::usable_size, None, None);
             (v.malloc_size_of)(&mut ops, dom_object)
         },
         Err(_e) => {
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index abd7ec4fa1b..2835b37329e 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -17,8 +17,6 @@
 //! a page runs its course and the script thread returns to processing events in the main event
 //! loop.
 
-extern crate itertools;
-
 use bluetooth_traits::BluetoothRequest;
 use canvas_traits::webgl::WebGLPipeline;
 use crate::devtools;
@@ -94,6 +92,7 @@ use headers_ext::LastModified;
 use headers_ext::ReferrerPolicy as ReferrerPolicyHeader;
 use hyper_serde::Serde;
 use ipc_channel::ipc::{self, IpcSender};
+use itertools;
 use js::glue::GetWindowProxyClass;
 use js::jsapi::{JSAutoCompartment, JSContext, JS_SetWrapObjectCallbacks};
 use js::jsapi::{JSTracer, SetWindowProxyClass};
@@ -260,7 +259,7 @@ pub enum MainThreadScriptMsg {
         pipeline_id: PipelineId,
         name: Atom,
         properties: Vec<Atom>,
-        painter: Box<Painter>,
+        painter: Box<dyn Painter>,
     },
     /// Dispatches a job queue.
     DispatchJobQueue { scope_url: ServoUrl },
@@ -314,7 +313,7 @@ impl QueuedTaskConversion for MainThreadScriptMsg {
     }
 }
 
-impl OpaqueSender<CommonScriptMsg> for Box<ScriptChan + Send> {
+impl OpaqueSender<CommonScriptMsg> for Box<dyn ScriptChan + Send> {
     fn send(&self, msg: CommonScriptMsg) {
         ScriptChan::send(&**self, msg).unwrap();
     }
@@ -367,7 +366,7 @@ impl ScriptChan for SendableMainThreadScriptChan {
         self.0.send(msg).map_err(|_| ())
     }
 
-    fn clone(&self) -> Box<ScriptChan + Send> {
+    fn clone(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(SendableMainThreadScriptChan((&self.0).clone()))
     }
 }
@@ -383,7 +382,7 @@ impl ScriptChan for MainThreadScriptChan {
             .map_err(|_| ())
     }
 
-    fn clone(&self) -> Box<ScriptChan + Send> {
+    fn clone(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(MainThreadScriptChan((&self.0).clone()))
     }
 }
@@ -501,7 +500,7 @@ pub struct ScriptThread {
     /// A job queue for Service Workers keyed by their scope url
     job_queue_map: Rc<JobQueue>,
     /// Image cache for this script thread.
-    image_cache: Arc<ImageCache>,
+    image_cache: Arc<dyn ImageCache>,
     /// A handle to the resource thread. This is an `Arc` to avoid running out of file descriptors if
     /// there are many iframes.
     resource_threads: ResourceThreads,
@@ -515,21 +514,21 @@ pub struct ScriptThread {
     /// events in the event queue.
     chan: MainThreadScriptChan,
 
-    dom_manipulation_task_sender: Box<ScriptChan>,
+    dom_manipulation_task_sender: Box<dyn ScriptChan>,
 
     media_element_task_sender: Sender<MainThreadScriptMsg>,
 
     user_interaction_task_sender: Sender<MainThreadScriptMsg>,
 
-    networking_task_sender: Box<ScriptChan>,
+    networking_task_sender: Box<dyn ScriptChan>,
 
     history_traversal_task_source: HistoryTraversalTaskSource,
 
-    file_reading_task_sender: Box<ScriptChan>,
+    file_reading_task_sender: Box<dyn ScriptChan>,
 
-    performance_timeline_task_sender: Box<ScriptChan>,
+    performance_timeline_task_sender: Box<dyn ScriptChan>,
 
-    remote_event_task_sender: Box<ScriptChan>,
+    remote_event_task_sender: Box<dyn ScriptChan>,
 
     /// A channel to hand out to threads that need to respond to a message from the script thread.
     control_chan: IpcSender<ConstellationControlMsg>,
@@ -913,7 +912,7 @@ impl ScriptThread {
         pipeline_id: PipelineId,
         name: Atom,
         properties: Vec<Atom>,
-        painter: Box<Painter>,
+        painter: Box<dyn Painter>,
     ) {
         let window = self.documents.borrow().find_window(pipeline_id);
         let window = match window {
diff --git a/components/script/task.rs b/components/script/task.rs
index 622da35567d..06137f90278 100644
--- a/components/script/task.rs
+++ b/components/script/task.rs
@@ -65,7 +65,7 @@ where
     }
 }
 
-impl fmt::Debug for TaskBox {
+impl fmt::Debug for dyn TaskBox {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
         fmt.debug_tuple(self.name())
             .field(&format_args!("..."))
diff --git a/components/script/task_queue.rs b/components/script/task_queue.rs
index 1160da51c96..4d5d041f24c 100644
--- a/components/script/task_queue.rs
+++ b/components/script/task_queue.rs
@@ -18,7 +18,7 @@ use std::default::Default;
 pub type QueuedTask = (
     Option<TrustedWorkerAddress>,
     ScriptThreadEventCategory,
-    Box<TaskBox>,
+    Box<dyn TaskBox>,
     Option<PipelineId>,
     TaskSourceName,
 );
diff --git a/components/script/task_source/dom_manipulation.rs b/components/script/task_source/dom_manipulation.rs
index fa6da31e6eb..35f4ac6dad5 100644
--- a/components/script/task_source/dom_manipulation.rs
+++ b/components/script/task_source/dom_manipulation.rs
@@ -16,7 +16,7 @@ use std::fmt;
 use std::result::Result;
 
 #[derive(JSTraceable)]
-pub struct DOMManipulationTaskSource(pub Box<ScriptChan + Send>, pub PipelineId);
+pub struct DOMManipulationTaskSource(pub Box<dyn ScriptChan + Send>, pub PipelineId);
 
 impl Clone for DOMManipulationTaskSource {
     fn clone(&self) -> DOMManipulationTaskSource {
diff --git a/components/script/task_source/file_reading.rs b/components/script/task_source/file_reading.rs
index 3c5b0bbcb69..39a18c6e1ab 100644
--- a/components/script/task_source/file_reading.rs
+++ b/components/script/task_source/file_reading.rs
@@ -11,7 +11,7 @@ use msg::constellation_msg::PipelineId;
 use std::sync::Arc;
 
 #[derive(JSTraceable)]
-pub struct FileReadingTaskSource(pub Box<ScriptChan + Send + 'static>, pub PipelineId);
+pub struct FileReadingTaskSource(pub Box<dyn ScriptChan + Send + 'static>, pub PipelineId);
 
 impl Clone for FileReadingTaskSource {
     fn clone(&self) -> FileReadingTaskSource {
diff --git a/components/script/task_source/history_traversal.rs b/components/script/task_source/history_traversal.rs
index 0bc5841b73c..c1bc6d26d83 100644
--- a/components/script/task_source/history_traversal.rs
+++ b/components/script/task_source/history_traversal.rs
@@ -16,7 +16,7 @@ impl ScriptChan for HistoryTraversalTaskSource {
             .map_err(|_| ())
     }
 
-    fn clone(&self) -> Box<ScriptChan + Send> {
+    fn clone(&self) -> Box<dyn ScriptChan + Send> {
         Box::new(HistoryTraversalTaskSource((&self.0).clone()))
     }
 }
diff --git a/components/script/task_source/networking.rs b/components/script/task_source/networking.rs
index a472a8f5691..fbf030c48b3 100644
--- a/components/script/task_source/networking.rs
+++ b/components/script/task_source/networking.rs
@@ -8,7 +8,7 @@ use crate::task_source::{TaskSource, TaskSourceName};
 use msg::constellation_msg::PipelineId;
 
 #[derive(JSTraceable)]
-pub struct NetworkingTaskSource(pub Box<ScriptChan + Send + 'static>, pub PipelineId);
+pub struct NetworkingTaskSource(pub Box<dyn ScriptChan + Send + 'static>, pub PipelineId);
 
 impl Clone for NetworkingTaskSource {
     fn clone(&self) -> NetworkingTaskSource {
diff --git a/components/script/task_source/performance_timeline.rs b/components/script/task_source/performance_timeline.rs
index f6c29880e98..8b2cef77e1c 100644
--- a/components/script/task_source/performance_timeline.rs
+++ b/components/script/task_source/performance_timeline.rs
@@ -16,7 +16,7 @@ use std::fmt;
 use std::result::Result;
 
 #[derive(JSTraceable)]
-pub struct PerformanceTimelineTaskSource(pub Box<ScriptChan + Send + 'static>, pub PipelineId);
+pub struct PerformanceTimelineTaskSource(pub Box<dyn ScriptChan + Send + 'static>, pub PipelineId);
 
 impl Clone for PerformanceTimelineTaskSource {
     fn clone(&self) -> PerformanceTimelineTaskSource {
diff --git a/components/script/task_source/remote_event.rs b/components/script/task_source/remote_event.rs
index e58f94d1645..89b9aef303e 100644
--- a/components/script/task_source/remote_event.rs
+++ b/components/script/task_source/remote_event.rs
@@ -8,7 +8,7 @@ use crate::task_source::{TaskSource, TaskSourceName};
 use msg::constellation_msg::PipelineId;
 
 #[derive(JSTraceable)]
-pub struct RemoteEventTaskSource(pub Box<ScriptChan + Send + 'static>, pub PipelineId);
+pub struct RemoteEventTaskSource(pub Box<dyn ScriptChan + Send + 'static>, pub PipelineId);
 
 impl Clone for RemoteEventTaskSource {
     fn clone(&self) -> RemoteEventTaskSource {
diff --git a/components/script/task_source/websocket.rs b/components/script/task_source/websocket.rs
index 9cb116155d1..c54a107fd79 100644
--- a/components/script/task_source/websocket.rs
+++ b/components/script/task_source/websocket.rs
@@ -8,7 +8,7 @@ use crate::task_source::{TaskSource, TaskSourceName};
 use msg::constellation_msg::PipelineId;
 
 #[derive(JSTraceable)]
-pub struct WebsocketTaskSource(pub Box<ScriptChan + Send + 'static>, pub PipelineId);
+pub struct WebsocketTaskSource(pub Box<dyn ScriptChan + Send + 'static>, pub PipelineId);
 
 impl Clone for WebsocketTaskSource {
     fn clone(&self) -> WebsocketTaskSource {
diff --git a/components/script/webdriver_handlers.rs b/components/script/webdriver_handlers.rs
index 30f1f12c6b5..f0ee142352b 100644
--- a/components/script/webdriver_handlers.rs
+++ b/components/script/webdriver_handlers.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use crate::cookie_rs::Cookie;
+use cookie::Cookie;
 use crate::dom::bindings::codegen::Bindings::CSSStyleDeclarationBinding::CSSStyleDeclarationMethods;
 use crate::dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
 use crate::dom::bindings::codegen::Bindings::ElementBinding::ElementMethods;
diff --git a/components/script_layout_interface/lib.rs b/components/script_layout_interface/lib.rs
index 58695a27750..23de1c5b0f5 100644
--- a/components/script_layout_interface/lib.rs
+++ b/components/script_layout_interface/lib.rs
@@ -9,34 +9,12 @@
 #![deny(unsafe_code)]
 #![feature(associated_type_defaults)]
 
-extern crate app_units;
-extern crate atomic_refcell;
-extern crate canvas_traits;
-extern crate cssparser;
-extern crate euclid;
-extern crate gfx_traits;
 #[macro_use]
 extern crate html5ever;
-extern crate ipc_channel;
-extern crate libc;
 #[macro_use]
 extern crate log;
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate metrics;
-extern crate msg;
-extern crate net_traits;
-extern crate profile_traits;
-extern crate range;
-extern crate script_traits;
-extern crate selectors;
-extern crate servo_arc;
-extern crate servo_atoms;
-extern crate servo_channel;
-extern crate servo_url;
-extern crate style;
-extern crate webrender_api;
 
 pub mod message;
 pub mod reporter;
@@ -53,6 +31,7 @@ use servo_url::ServoUrl;
 use std::ptr::NonNull;
 use std::sync::atomic::AtomicIsize;
 use style::data::ElementData;
+use webrender_api;
 
 #[repr(C)]
 pub struct StyleData {
diff --git a/components/script_layout_interface/message.rs b/components/script_layout_interface/message.rs
index 01edca28a77..5c504d06e84 100644
--- a/components/script_layout_interface/message.rs
+++ b/components/script_layout_interface/message.rs
@@ -42,7 +42,7 @@ pub enum Msg {
     Reflow(ScriptReflow),
 
     /// Get an RPC interface.
-    GetRPC(Sender<Box<LayoutRPC + Send>>),
+    GetRPC(Sender<Box<dyn LayoutRPC + Send>>),
 
     /// Requests that the layout thread render the next frame of all animations.
     TickAnimations,
@@ -94,7 +94,7 @@ pub enum Msg {
     UpdateScrollStateFromScript(ScrollState),
 
     /// Tells layout that script has added some paint worklet modules.
-    RegisterPaint(Atom, Vec<Atom>, Box<Painter>),
+    RegisterPaint(Atom, Vec<Atom>, Box<dyn Painter>),
 
     /// Send to layout the precise time when the navigation started.
     SetNavigationStart(u64),
@@ -214,7 +214,7 @@ pub struct NewLayoutThreadInfo {
     pub pipeline_port: IpcReceiver<LayoutControlMsg>,
     pub constellation_chan: IpcSender<ConstellationMsg>,
     pub script_chan: IpcSender<ConstellationControlMsg>,
-    pub image_cache: Arc<ImageCache>,
+    pub image_cache: Arc<dyn ImageCache>,
     pub content_process_shutdown_chan: Option<IpcSender<()>>,
     pub layout_threads: usize,
     pub paint_time_metrics: PaintTimeMetrics,
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index acc261033c9..00a60d1f3e8 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -9,35 +9,12 @@
 #![deny(missing_docs)]
 #![deny(unsafe_code)]
 
-extern crate bluetooth_traits;
-extern crate canvas_traits;
-extern crate cookie as cookie_rs;
-extern crate devtools_traits;
-extern crate embedder_traits;
-extern crate euclid;
-extern crate gfx_traits;
-extern crate http;
-extern crate hyper;
-extern crate hyper_serde;
-extern crate ipc_channel;
-extern crate keyboard_types;
-extern crate libc;
 #[macro_use]
 extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate msg;
-extern crate net_traits;
-extern crate profile_traits;
 #[macro_use]
 extern crate serde;
-extern crate servo_atoms;
-extern crate servo_channel;
-extern crate servo_url;
-extern crate style_traits;
-extern crate time;
-extern crate webrender_api;
-extern crate webvr_traits;
 
 mod script_msg;
 pub mod webdriver_msg;
@@ -575,7 +552,7 @@ pub struct InitialScriptState {
     /// A channel to the bluetooth thread.
     pub bluetooth_thread: IpcSender<BluetoothRequest>,
     /// The image cache for this script thread.
-    pub image_cache: Arc<ImageCache>,
+    pub image_cache: Arc<dyn ImageCache>,
     /// A channel to the time profiler thread.
     pub time_profiler_chan: profile_traits::time::ProfilerChan,
     /// A channel to the memory profiler thread.
@@ -863,7 +840,7 @@ pub trait Painter: SpeculativePainter {
     ) -> Result<DrawAPaintImageResult, PaintWorkletError>;
 }
 
-impl fmt::Debug for Painter {
+impl fmt::Debug for dyn Painter {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
         fmt.debug_tuple("Painter")
             .field(&format_args!(".."))
diff --git a/components/script_traits/webdriver_msg.rs b/components/script_traits/webdriver_msg.rs
index 5e49864eb09..4a7647a9e24 100644
--- a/components/script_traits/webdriver_msg.rs
+++ b/components/script_traits/webdriver_msg.rs
@@ -4,7 +4,7 @@
 
 #![allow(missing_docs)]
 
-use crate::cookie_rs::Cookie;
+use cookie::Cookie;
 use euclid::Rect;
 use hyper_serde::Serde;
 use ipc_channel::ipc::IpcSender;
diff --git a/components/servo/lib.rs b/components/servo/lib.rs
index 94fd50508af..ce3ee0962b1 100644
--- a/components/servo/lib.rs
+++ b/components/servo/lib.rs
@@ -17,49 +17,40 @@
 //! `Servo` is fed events from a generic type that implements the
 //! `WindowMethods` trait.
 
-extern crate env_logger;
-#[cfg(all(not(target_os = "windows"), not(target_os = "ios")))]
-extern crate gaol;
-extern crate gleam;
 #[macro_use]
 extern crate log;
 
-pub extern crate bluetooth;
-pub extern crate bluetooth_traits;
-pub extern crate canvas;
-pub extern crate canvas_traits;
-pub extern crate compositing;
-pub extern crate constellation;
-pub extern crate debugger;
-pub extern crate devtools;
-pub extern crate devtools_traits;
-pub extern crate embedder_traits;
-pub extern crate euclid;
-pub extern crate gfx;
-pub extern crate ipc_channel;
-pub extern crate layout_thread;
-pub extern crate msg;
-pub extern crate net;
-pub extern crate net_traits;
-pub extern crate profile;
-pub extern crate profile_traits;
-pub extern crate script;
-pub extern crate script_layout_interface;
-pub extern crate script_traits;
-pub extern crate servo_channel;
-pub extern crate servo_config;
-pub extern crate servo_geometry;
-pub extern crate servo_url;
-pub extern crate style;
-pub extern crate style_traits;
-pub extern crate webrender_api;
-pub extern crate webvr;
-pub extern crate webvr_traits;
-
-#[cfg(feature = "webdriver")]
-extern crate webdriver_server;
-
-extern crate webrender;
+pub use bluetooth;
+pub use bluetooth_traits;
+pub use canvas;
+pub use canvas_traits;
+pub use compositing;
+pub use constellation;
+pub use debugger;
+pub use devtools;
+pub use devtools_traits;
+pub use embedder_traits;
+pub use euclid;
+pub use gfx;
+pub use ipc_channel;
+pub use layout_thread;
+pub use msg;
+pub use net;
+pub use net_traits;
+pub use profile;
+pub use profile_traits;
+pub use script;
+pub use script_layout_interface;
+pub use script_traits;
+pub use servo_channel;
+pub use servo_config;
+pub use servo_geometry;
+pub use servo_url;
+pub use style;
+pub use style_traits;
+pub use webrender_api;
+pub use webvr;
+pub use webvr_traits;
 
 #[cfg(feature = "webdriver")]
 fn webdriver(port: u16, constellation: Sender<ConstellationMsg>) {
@@ -170,7 +161,7 @@ where
             let recorder = if opts.webrender_record {
                 let record_path = PathBuf::from("wr-record.bin");
                 let recorder = Box::new(webrender::BinaryRecorder::new(&record_path));
-                Some(recorder as Box<webrender::ApiRecordingReceiver>)
+                Some(recorder as Box<dyn webrender::ApiRecordingReceiver>)
             } else {
                 None
             };
@@ -458,7 +449,7 @@ where
 }
 
 fn create_embedder_channel(
-    event_loop_waker: Box<EventLoopWaker>,
+    event_loop_waker: Box<dyn EventLoopWaker>,
 ) -> (EmbedderProxy, EmbedderReceiver) {
     let (sender, receiver) = channel();
     (
@@ -471,7 +462,7 @@ fn create_embedder_channel(
 }
 
 fn create_compositor_channel(
-    event_loop_waker: Box<EventLoopWaker>,
+    event_loop_waker: Box<dyn EventLoopWaker>,
 ) -> (CompositorProxy, CompositorReceiver) {
     let (sender, receiver) = channel();
     (
@@ -495,7 +486,7 @@ fn create_constellation(
     webrender: &mut webrender::Renderer,
     webrender_document: webrender_api::DocumentId,
     webrender_api_sender: webrender_api::RenderApiSender,
-    window_gl: Rc<gl::Gl>,
+    window_gl: Rc<dyn gl::Gl>,
 ) -> (Sender<ConstellationMsg>, SWManagerSenders) {
     let bluetooth_thread: IpcSender<BluetoothRequest> =
         BluetoothThreadFactory::new(embedder_proxy.clone());
diff --git a/components/url/lib.rs b/components/url/lib.rs
index 069fc767691..7ec15b05d7b 100644
--- a/components/url/lib.rs
+++ b/components/url/lib.rs
@@ -12,10 +12,6 @@ extern crate malloc_size_of;
 extern crate malloc_size_of_derive;
 #[macro_use]
 extern crate serde;
-extern crate servo_rand;
-extern crate url;
-extern crate url_serde;
-extern crate uuid;
 
 pub mod origin;
 
@@ -27,6 +23,7 @@ use std::ops::{Index, Range, RangeFrom, RangeFull, RangeTo};
 use std::path::Path;
 use std::sync::Arc;
 use url::{Position, Url};
+use url_serde;
 
 pub use url::Host;
 
diff --git a/components/webdriver_server/lib.rs b/components/webdriver_server/lib.rs
index c199eddee28..40339bf14d9 100644
--- a/components/webdriver_server/lib.rs
+++ b/components/webdriver_server/lib.rs
@@ -6,30 +6,15 @@
 #![crate_type = "rlib"]
 #![deny(unsafe_code)]
 
-extern crate base64;
-extern crate cookie as cookie_rs;
-extern crate euclid;
-extern crate hyper;
-extern crate image;
-extern crate ipc_channel;
-extern crate keyboard_types;
 #[macro_use]
 extern crate log;
-extern crate msg;
-extern crate net_traits;
-extern crate regex;
-extern crate script_traits;
 #[macro_use]
 extern crate serde;
-extern crate serde_json;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_url;
-extern crate uuid;
-extern crate webdriver;
 
 mod keys;
 
+use base64;
+use cookie;
 use crate::keys::keycodes_to_keys;
 use euclid::TypedSize2D;
 use hyper::Method;
@@ -45,7 +30,7 @@ use script_traits::webdriver_msg::{
 use script_traits::{ConstellationMsg, LoadData, WebDriverCommandMsg};
 use serde::de::{Deserialize, Deserializer, MapAccess, Visitor};
 use serde::ser::{Serialize, Serializer};
-use serde_json::Value;
+use serde_json::{self, Value};
 use servo_channel::Sender;
 use servo_config::prefs::{PrefValue, PREFS};
 use servo_url::ServoUrl;
@@ -91,7 +76,7 @@ fn extension_routes() -> Vec<(Method, &'static str, ServoExtensionRoute)> {
     ];
 }
 
-fn cookie_msg_to_cookie(cookie: cookie_rs::Cookie) -> Cookie {
+fn cookie_msg_to_cookie(cookie: cookie::Cookie) -> Cookie {
     Cookie {
         name: cookie.name().to_owned(),
         value: cookie.value().to_owned(),
@@ -920,7 +905,7 @@ impl Handler {
     ) -> WebDriverResult<WebDriverResponse> {
         let (sender, receiver) = ipc::channel().unwrap();
 
-        let cookie = cookie_rs::Cookie::build(params.name.to_owned(), params.value.to_owned())
+        let cookie = cookie::Cookie::build(params.name.to_owned(), params.value.to_owned())
             .secure(params.secure)
             .http_only(params.httpOnly);
         let cookie = match params.domain {
diff --git a/components/webvr/lib.rs b/components/webvr/lib.rs
index 6b84eb6e1a9..fd2c70c81c2 100644
--- a/components/webvr/lib.rs
+++ b/components/webvr/lib.rs
@@ -4,17 +4,8 @@
 
 #![deny(unsafe_code)]
 
-extern crate canvas_traits;
-extern crate euclid;
-extern crate ipc_channel;
 #[macro_use]
 extern crate log;
-extern crate msg;
-extern crate rust_webvr;
-extern crate script_traits;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate webvr_traits;
 
 mod webvr_thread;
 pub use crate::webvr_thread::{WebVRCompositorHandler, WebVRThread};
diff --git a/components/webvr/webvr_thread.rs b/components/webvr/webvr_thread.rs
index 4a264e073c0..1a46a33c9cc 100644
--- a/components/webvr/webvr_thread.rs
+++ b/components/webvr/webvr_thread.rs
@@ -347,7 +347,7 @@ impl WebVRThread {
 ///    * WebVRThread and its VRDisplays are destroyed after all tabs are dropped and the browser is about to exit.
 ///      WebVRThread is closed using the Exit message.
 
-pub struct WebVRCompositor(*mut VRDisplay);
+pub struct WebVRCompositor(*mut dyn VRDisplay);
 pub struct WebVRCompositorHandler {
     compositors: HashMap<webgl::WebVRDeviceId, WebVRCompositor>,
     webvr_thread_receiver: Receiver<Option<WebVRCompositor>>,
diff --git a/components/webvr_traits/lib.rs b/components/webvr_traits/lib.rs
index d1d33111eb0..299e7090fc3 100644
--- a/components/webvr_traits/lib.rs
+++ b/components/webvr_traits/lib.rs
@@ -4,29 +4,27 @@
 
 #![deny(unsafe_code)]
 
-extern crate ipc_channel;
-extern crate msg;
 #[macro_use]
 extern crate serde;
-pub extern crate rust_webvr_api as webvr;
 
 mod webvr_traits;
 
-pub use crate::webvr::VRDisplayCapabilities as WebVRDisplayCapabilities;
-pub use crate::webvr::VRDisplayData as WebVRDisplayData;
-pub use crate::webvr::VRDisplayEvent as WebVRDisplayEvent;
-pub use crate::webvr::VRDisplayEventReason as WebVRDisplayEventReason;
-pub use crate::webvr::VREvent as WebVREvent;
-pub use crate::webvr::VREye as WebVREye;
-pub use crate::webvr::VREyeParameters as WebVREyeParameters;
-pub use crate::webvr::VRFieldOfView as WebVRFieldOfView;
-pub use crate::webvr::VRFrameData as WebVRFrameData;
-pub use crate::webvr::VRGamepadButton as WebVRGamepadButton;
-pub use crate::webvr::VRGamepadData as WebVRGamepadData;
-pub use crate::webvr::VRGamepadEvent as WebVRGamepadEvent;
-pub use crate::webvr::VRGamepadHand as WebVRGamepadHand;
-pub use crate::webvr::VRGamepadState as WebVRGamepadState;
-pub use crate::webvr::VRLayer as WebVRLayer;
-pub use crate::webvr::VRPose as WebVRPose;
-pub use crate::webvr::VRStageParameters as WebVRStageParameters;
 pub use crate::webvr_traits::{WebVRMsg, WebVRResult};
+pub use rust_webvr_api as webvr;
+pub use rust_webvr_api::VRDisplayCapabilities as WebVRDisplayCapabilities;
+pub use rust_webvr_api::VRDisplayData as WebVRDisplayData;
+pub use rust_webvr_api::VRDisplayEvent as WebVRDisplayEvent;
+pub use rust_webvr_api::VRDisplayEventReason as WebVRDisplayEventReason;
+pub use rust_webvr_api::VREvent as WebVREvent;
+pub use rust_webvr_api::VREye as WebVREye;
+pub use rust_webvr_api::VREyeParameters as WebVREyeParameters;
+pub use rust_webvr_api::VRFieldOfView as WebVRFieldOfView;
+pub use rust_webvr_api::VRFrameData as WebVRFrameData;
+pub use rust_webvr_api::VRGamepadButton as WebVRGamepadButton;
+pub use rust_webvr_api::VRGamepadData as WebVRGamepadData;
+pub use rust_webvr_api::VRGamepadEvent as WebVRGamepadEvent;
+pub use rust_webvr_api::VRGamepadHand as WebVRGamepadHand;
+pub use rust_webvr_api::VRGamepadState as WebVRGamepadState;
+pub use rust_webvr_api::VRLayer as WebVRLayer;
+pub use rust_webvr_api::VRPose as WebVRPose;
+pub use rust_webvr_api::VRStageParameters as WebVRStageParameters;
diff --git a/components/webvr_traits/webvr_traits.rs b/components/webvr_traits/webvr_traits.rs
index e8d6b7330a6..5a9f0a2e6ad 100644
--- a/components/webvr_traits/webvr_traits.rs
+++ b/components/webvr_traits/webvr_traits.rs
@@ -2,9 +2,9 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use crate::webvr::*;
 use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::PipelineId;
+use rust_webvr_api::*;
 
 pub type WebVRResult<T> = Result<T, String>;
 
diff --git a/ports/libsimpleservo/build.rs b/ports/libsimpleservo/build.rs
index 0ba96d6b7a8..116a24b665a 100644
--- a/ports/libsimpleservo/build.rs
+++ b/ports/libsimpleservo/build.rs
@@ -2,9 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate cc;
-extern crate gl_generator;
-
 use gl_generator::{Api, Fallbacks, Profile, Registry};
 use std::env;
 use std::fs::File;
diff --git a/ports/libsimpleservo/src/api.rs b/ports/libsimpleservo/src/api.rs
index 1c374531612..4e6a168a97d 100644
--- a/ports/libsimpleservo/src/api.rs
+++ b/ports/libsimpleservo/src/api.rs
@@ -106,10 +106,10 @@ pub fn servo_version() -> String {
 /// In the future, this will be done in multiple steps.
 pub fn init(
     init_opts: InitOptions,
-    gl: Rc<gl::Gl>,
-    waker: Box<EventLoopWaker>,
-    readfile: Box<ReadFileTrait + Send + Sync>,
-    callbacks: Box<HostTrait>,
+    gl: Rc<dyn gl::Gl>,
+    waker: Box<dyn EventLoopWaker>,
+    readfile: Box<dyn ReadFileTrait + Send + Sync>,
+    callbacks: Box<dyn HostTrait>,
 ) -> Result<(), &'static str> {
     resources::set(Box::new(ResourceReader(readfile)));
 
@@ -444,9 +444,9 @@ impl ServoGlue {
 }
 
 struct ServoCallbacks {
-    waker: Box<EventLoopWaker>,
-    gl: Rc<gl::Gl>,
-    host_callbacks: Box<HostTrait>,
+    waker: Box<dyn EventLoopWaker>,
+    gl: Rc<dyn gl::Gl>,
+    host_callbacks: Box<dyn HostTrait>,
     width: Cell<u32>,
     height: Cell<u32>,
     density: f32,
@@ -464,12 +464,12 @@ impl WindowMethods for ServoCallbacks {
         self.host_callbacks.flush();
     }
 
-    fn create_event_loop_waker(&self) -> Box<EventLoopWaker> {
+    fn create_event_loop_waker(&self) -> Box<dyn EventLoopWaker> {
         debug!("WindowMethods::create_event_loop_waker");
         self.waker.clone()
     }
 
-    fn gl(&self) -> Rc<gl::Gl> {
+    fn gl(&self) -> Rc<dyn gl::Gl> {
         debug!("WindowMethods::gl");
         self.gl.clone()
     }
@@ -493,7 +493,7 @@ impl WindowMethods for ServoCallbacks {
     }
 }
 
-struct ResourceReader(Box<ReadFileTrait + Send + Sync>);
+struct ResourceReader(Box<dyn ReadFileTrait + Send + Sync>);
 
 impl resources::ResourceReaderMethods for ResourceReader {
     fn read(&self, file: Resource) -> Vec<u8> {
diff --git a/ports/libsimpleservo/src/capi.rs b/ports/libsimpleservo/src/capi.rs
index bcd1d247854..c71a45a08b2 100644
--- a/ports/libsimpleservo/src/capi.rs
+++ b/ports/libsimpleservo/src/capi.rs
@@ -64,7 +64,7 @@ pub extern "C" fn servo_version() -> *const c_char {
 
 fn init(
     opts: CInitOptions,
-    gl: Rc<gl::Gl>,
+    gl: Rc<dyn gl::Gl>,
     wakeup: extern "C" fn(),
     readfile: extern "C" fn(*const c_char) -> *const c_char,
     callbacks: CHostCallbacks,
@@ -238,7 +238,7 @@ impl WakeupCallback {
 }
 
 impl EventLoopWaker for WakeupCallback {
-    fn clone(&self) -> Box<EventLoopWaker + Send> {
+    fn clone(&self) -> Box<dyn EventLoopWaker + Send> {
         Box::new(WakeupCallback(self.0))
     }
     fn wake(&self) {
diff --git a/ports/libsimpleservo/src/gl_glue.rs b/ports/libsimpleservo/src/gl_glue.rs
index 3d8903a4e10..f819105ed4f 100644
--- a/ports/libsimpleservo/src/gl_glue.rs
+++ b/ports/libsimpleservo/src/gl_glue.rs
@@ -89,7 +89,7 @@ pub mod egl {
 pub mod gl {
     use servo::gl::Gl;
     use std::rc::Rc;
-    pub fn init() -> Result<Rc<Gl>, &'static str> {
+    pub fn init() -> Result<Rc<dyn Gl>, &'static str> {
         // FIXME: Add an OpenGL version
         unimplemented!()
     }
diff --git a/ports/libsimpleservo/src/lib.rs b/ports/libsimpleservo/src/lib.rs
index 6898f542a8c..cbe24f77c9f 100644
--- a/ports/libsimpleservo/src/lib.rs
+++ b/ports/libsimpleservo/src/lib.rs
@@ -2,20 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#[cfg(target_os = "android")]
-extern crate android_injected_glue;
-#[cfg(target_os = "android")]
-extern crate android_logger;
-#[cfg(target_os = "android")]
-extern crate jni;
-#[cfg(any(target_os = "android", target_os = "windows"))]
-extern crate libc;
 #[macro_use]
 extern crate log;
-extern crate serde_json;
-extern crate servo;
-#[cfg(target_os = "windows")]
-extern crate winapi;
 
 mod api;
 mod gl_glue;
diff --git a/ports/servo/glutin_app/window.rs b/ports/servo/glutin_app/window.rs
index 7f962ca9ce3..655063d37eb 100644
--- a/ports/servo/glutin_app/window.rs
+++ b/ports/servo/glutin_app/window.rs
@@ -153,7 +153,7 @@ pub struct Window {
     last_pressed: Cell<Option<KeyboardEvent>>,
     animation_state: Cell<AnimationState>,
     fullscreen: Cell<bool>,
-    gl: Rc<gl::Gl>,
+    gl: Rc<dyn gl::Gl>,
     suspended: Cell<bool>,
 }
 
@@ -675,7 +675,7 @@ impl Window {
 }
 
 impl WindowMethods for Window {
-    fn gl(&self) -> Rc<gl::Gl> {
+    fn gl(&self) -> Rc<dyn gl::Gl> {
         self.gl.clone()
     }
 
@@ -738,7 +738,7 @@ impl WindowMethods for Window {
         }
     }
 
-    fn create_event_loop_waker(&self) -> Box<EventLoopWaker> {
+    fn create_event_loop_waker(&self) -> Box<dyn EventLoopWaker> {
         struct GlutinEventLoopWaker {
             proxy: Option<Arc<winit::EventsLoopProxy>>,
         }
@@ -762,7 +762,7 @@ impl WindowMethods for Window {
                     }
                 }
             }
-            fn clone(&self) -> Box<EventLoopWaker + Send> {
+            fn clone(&self) -> Box<dyn EventLoopWaker + Send> {
                 Box::new(GlutinEventLoopWaker {
                     proxy: self.proxy.clone(),
                 })
diff --git a/ports/servo/non_android_main.rs b/ports/servo/non_android_main.rs
index f246c8d3e4f..80e3f18a72a 100644
--- a/ports/servo/non_android_main.rs
+++ b/ports/servo/non_android_main.rs
@@ -2,32 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate backtrace;
-extern crate euclid;
-#[cfg(target_os = "windows")]
-extern crate gdi32;
-extern crate gleam;
-extern crate glutin;
-extern crate keyboard_types;
-#[macro_use]
-extern crate lazy_static;
-#[cfg(any(target_os = "linux", target_os = "macos"))]
-extern crate osmesa_sys;
-extern crate servo;
-#[cfg(feature = "unstable")]
-#[macro_use]
-extern crate sig;
-#[cfg(any(
-    target_os = "macos",
-    target_os = "linux",
-    target_os = "windows"
-))]
-extern crate tinyfiledialogs;
-#[cfg(target_os = "windows")]
-extern crate user32;
-#[cfg(target_os = "windows")]
-extern crate winapi;
-extern crate winit;
+#[macro_use] extern crate lazy_static;
+#[cfg(feature = "unstable")] #[macro_use] extern crate sig;
 
 // The window backed by glutin
 mod glutin_app;
diff --git a/support/rust-task_info/build.rs b/support/rust-task_info/build.rs
index e20f2723a80..94ef6005df5 100644
--- a/support/rust-task_info/build.rs
+++ b/support/rust-task_info/build.rs
@@ -2,8 +2,6 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern crate cc;
-
 fn main() {
     cc::Build::new()
         .file("src/task_info.c")
diff --git a/tests/unit/metrics/lib.rs b/tests/unit/metrics/lib.rs
index e5f99bff746..bb1ee41a069 100644
--- a/tests/unit/metrics/lib.rs
+++ b/tests/unit/metrics/lib.rs
@@ -4,15 +4,5 @@
 
 #![cfg(test)]
 
-extern crate gfx_traits;
-extern crate ipc_channel;
-extern crate layout;
-extern crate metrics;
-extern crate msg;
-extern crate profile_traits;
-extern crate servo_url;
-extern crate time;
-extern crate webrender_api;
-
 mod interactive_time;
 mod paint_time;
diff --git a/tests/unit/profile/Cargo.toml b/tests/unit/profile/Cargo.toml
index 9e608a7c3ce..fca955ca052 100644
--- a/tests/unit/profile/Cargo.toml
+++ b/tests/unit/profile/Cargo.toml
@@ -14,8 +14,5 @@ doctest = false
 ipc-channel = "0.11"
 profile = {path = "../../../components/profile"}
 profile_traits = {path = "../../../components/profile_traits"}
-
-# Work around https://github.com/alexcrichton/jemallocator/issues/19
-servo_allocator = {path = "../../../components/allocator"}
 servo_config = {path = "../../../components/config"}
 
diff --git a/tests/unit/profile/lib.rs b/tests/unit/profile/lib.rs
index a67e211ad7b..3d8c49b1754 100644
--- a/tests/unit/profile/lib.rs
+++ b/tests/unit/profile/lib.rs
@@ -4,10 +4,4 @@
 
 #![cfg(test)]
 
-extern crate ipc_channel;
-extern crate profile;
-extern crate profile_traits;
-extern crate servo_allocator;
-extern crate servo_config;
-
 mod time;
diff --git a/tests/unit/script/lib.rs b/tests/unit/script/lib.rs
index 0251144dd30..0e68becec17 100644
--- a/tests/unit/script/lib.rs
+++ b/tests/unit/script/lib.rs
@@ -3,15 +3,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #[cfg(test)]
-extern crate euclid;
-#[cfg(test)]
-extern crate keyboard_types;
-#[cfg(test)]
-extern crate script;
-#[cfg(test)]
-extern crate servo_url;
-
-#[cfg(test)]
 mod headers;
 #[cfg(test)]
 mod htmlareaelement;
author	Simon Sapin <simon.sapin@exyr.org>	2018-11-01 21:43:04 +0100
committer	Simon Sapin <simon.sapin@exyr.org>	2018-11-08 09:28:00 +0100
commit	2012be4a8bd97f2fd69f986c8fffb1af1eec21dc (patch)
tree	c9f1ef91146253f72987cb1436866523880965e0
parent	b1fd6237d1304f3d57abdafd3e6e738c1ece9f83 (diff)
download	servo-2012be4a8bd97f2fd69f986c8fffb1af1eec21dc.tar.gz servo-2012be4a8bd97f2fd69f986c8fffb1af1eec21dc.zip