api: Flatten and simplify Servo preferences (#34966)

Flatten and simplify Servo's preferences code. In addition, have both
preferences and options passed in as arguments to `Servo::new()` and
make sure not to use the globally set preferences in `servoshell` (as
much as possible now).

Instead of a complex procedural macro to generate preferences, just
expose a very simple derive macro that adds string based getters and
setters.

- All command-line parsing is moved to servoshell.
- There is no longer the concept of a missing preference.
- Preferences no longer have to be part of the resources bundle because
  they now have reasonable default values.
- servoshell specific preferences are no longer part of the preferences
  exposed by the Servo API.

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

139 files changed, 217 insertions, 217 deletions

diff --git a/components/script/dom/webidls/AbortController.webidl b/components/script/dom/webidls/AbortController.webidl
index faeaf9cbd44..cef49010d3c 100644
--- a/components/script/dom/webidls/AbortController.webidl
+++ b/components/script/dom/webidls/AbortController.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://dom.spec.whatwg.org/#interface-abortcontroller
-[Exposed=*, Pref="dom.abort_controller.enabled"]
+[Exposed=*, Pref="dom_abort_controller_enabled"]
 interface AbortController {
   constructor();
 
diff --git a/components/script/dom/webidls/ActivatableElement.webidl b/components/script/dom/webidls/ActivatableElement.webidl
index e9d959c8470..99a250a4b55 100644
--- a/components/script/dom/webidls/ActivatableElement.webidl
+++ b/components/script/dom/webidls/ActivatableElement.webidl
@@ -7,9 +7,9 @@
 // web pages.
 [Exposed=(Window,Worker)]
 interface mixin ActivatableElement {
-  [Throws, Pref="dom.testing.element.activation.enabled"]
+  [Throws, Pref="dom_testing_element_activation_enabled"]
   undefined enterFormalActivationState();
 
-  [Throws, Pref="dom.testing.element.activation.enabled"]
+  [Throws, Pref="dom_testing_element_activation_enabled"]
   undefined exitFormalActivationState();
 };
diff --git a/components/script/dom/webidls/Bluetooth.webidl b/components/script/dom/webidls/Bluetooth.webidl
index e5e135c0577..65ce8ea79b3 100644
--- a/components/script/dom/webidls/Bluetooth.webidl
+++ b/components/script/dom/webidls/Bluetooth.webidl
@@ -25,7 +25,7 @@ dictionary RequestDeviceOptions {
   boolean acceptAllDevices = false;
 };
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface Bluetooth : EventTarget {
   [SecureContext]
   Promise<boolean> getAvailability();
diff --git a/components/script/dom/webidls/BluetoothAdvertisingEvent.webidl b/components/script/dom/webidls/BluetoothAdvertisingEvent.webidl
index a7dd3fe947f..c6f3c6a8480 100644
--- a/components/script/dom/webidls/BluetoothAdvertisingEvent.webidl
+++ b/components/script/dom/webidls/BluetoothAdvertisingEvent.webidl
@@ -10,7 +10,7 @@
 interface BluetoothServiceDataMap {
   readonly maplike<UUID, DataView>;
 };*/
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothAdvertisingEvent : Event {
   [Throws] constructor(DOMString type, BluetoothAdvertisingEventInit init);
   [SameObject]
diff --git a/components/script/dom/webidls/BluetoothCharacteristicProperties.webidl b/components/script/dom/webidls/BluetoothCharacteristicProperties.webidl
index 124f881a2e0..fb812ff7c46 100644
--- a/components/script/dom/webidls/BluetoothCharacteristicProperties.webidl
+++ b/components/script/dom/webidls/BluetoothCharacteristicProperties.webidl
@@ -4,7 +4,7 @@
 
 // https://webbluetoothcg.github.io/web-bluetooth/#characteristicproperties
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothCharacteristicProperties {
   readonly attribute boolean broadcast;
   readonly attribute boolean read;
diff --git a/components/script/dom/webidls/BluetoothDevice.webidl b/components/script/dom/webidls/BluetoothDevice.webidl
index c514132140d..f9cb44dda5a 100644
--- a/components/script/dom/webidls/BluetoothDevice.webidl
+++ b/components/script/dom/webidls/BluetoothDevice.webidl
@@ -4,7 +4,7 @@
 
 // https://webbluetoothcg.github.io/web-bluetooth/#bluetoothdevice
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothDevice : EventTarget {
   readonly attribute DOMString id;
   readonly attribute DOMString? name;
diff --git a/components/script/dom/webidls/BluetoothPermissionResult.webidl b/components/script/dom/webidls/BluetoothPermissionResult.webidl
index 95c06797aef..67822fc55cf 100644
--- a/components/script/dom/webidls/BluetoothPermissionResult.webidl
+++ b/components/script/dom/webidls/BluetoothPermissionResult.webidl
@@ -12,7 +12,7 @@ dictionary BluetoothPermissionDescriptor : PermissionDescriptor {
   boolean acceptAllDevices = false;
 };
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothPermissionResult : PermissionStatus {
   // attribute FrozenArray<BluetoothDevice> devices;
   // Workaround until FrozenArray get implemented.
diff --git a/components/script/dom/webidls/BluetoothRemoteGATTCharacteristic.webidl b/components/script/dom/webidls/BluetoothRemoteGATTCharacteristic.webidl
index 9f41d2450f9..9e0140d8129 100644
--- a/components/script/dom/webidls/BluetoothRemoteGATTCharacteristic.webidl
+++ b/components/script/dom/webidls/BluetoothRemoteGATTCharacteristic.webidl
@@ -4,7 +4,7 @@
 
 // https://webbluetoothcg.github.io/web-bluetooth/#bluetoothremotegattcharacteristic
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothRemoteGATTCharacteristic : EventTarget {
   [SameObject]
   readonly attribute BluetoothRemoteGATTService service;
diff --git a/components/script/dom/webidls/BluetoothRemoteGATTDescriptor.webidl b/components/script/dom/webidls/BluetoothRemoteGATTDescriptor.webidl
index 29cbc3040a4..31e19a850fc 100644
--- a/components/script/dom/webidls/BluetoothRemoteGATTDescriptor.webidl
+++ b/components/script/dom/webidls/BluetoothRemoteGATTDescriptor.webidl
@@ -4,7 +4,7 @@
 
 // http://webbluetoothcg.github.io/web-bluetooth/#bluetoothremotegattdescriptor
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothRemoteGATTDescriptor {
   [SameObject]
   readonly attribute BluetoothRemoteGATTCharacteristic characteristic;
diff --git a/components/script/dom/webidls/BluetoothRemoteGATTServer.webidl b/components/script/dom/webidls/BluetoothRemoteGATTServer.webidl
index e46cef4a079..3d60ace070f 100644
--- a/components/script/dom/webidls/BluetoothRemoteGATTServer.webidl
+++ b/components/script/dom/webidls/BluetoothRemoteGATTServer.webidl
@@ -4,7 +4,7 @@
 
 //https://webbluetoothcg.github.io/web-bluetooth/#bluetoothremotegattserver
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothRemoteGATTServer {
   [SameObject]
   readonly attribute BluetoothDevice device;
diff --git a/components/script/dom/webidls/BluetoothRemoteGATTService.webidl b/components/script/dom/webidls/BluetoothRemoteGATTService.webidl
index 7e9f624dd1c..e505ae3aabe 100644
--- a/components/script/dom/webidls/BluetoothRemoteGATTService.webidl
+++ b/components/script/dom/webidls/BluetoothRemoteGATTService.webidl
@@ -4,7 +4,7 @@
 
 // https://webbluetoothcg.github.io/web-bluetooth/#bluetoothremotegattservice
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothRemoteGATTService : EventTarget {
   [SameObject]
   readonly attribute BluetoothDevice device;
diff --git a/components/script/dom/webidls/BluetoothUUID.webidl b/components/script/dom/webidls/BluetoothUUID.webidl
index dde82d3acb7..5ee501bf6e6 100644
--- a/components/script/dom/webidls/BluetoothUUID.webidl
+++ b/components/script/dom/webidls/BluetoothUUID.webidl
@@ -4,7 +4,7 @@
 
 // https://webbluetoothcg.github.io/web-bluetooth/#bluetoothuuid
 
-[Exposed=Window, Pref="dom.bluetooth.enabled"]
+[Exposed=Window, Pref="dom_bluetooth_enabled"]
 interface BluetoothUUID {
   [Throws]
   static UUID getService(BluetoothServiceUUID name);
diff --git a/components/script/dom/webidls/CSS.webidl b/components/script/dom/webidls/CSS.webidl
index 15049ae7539..2a199569cd8 100644
--- a/components/script/dom/webidls/CSS.webidl
+++ b/components/script/dom/webidls/CSS.webidl
@@ -20,5 +20,5 @@ partial interface CSS {
 
 // https://drafts.css-houdini.org/css-paint-api-1/#paint-worklet
 partial interface CSS {
-    [SameObject, Pref="dom.worklet.enabled"] static readonly attribute Worklet paintWorklet;
+    [SameObject, Pref="dom_worklet_enabled"] static readonly attribute Worklet paintWorklet;
 };
diff --git a/components/script/dom/webidls/CSSStyleValue.webidl b/components/script/dom/webidls/CSSStyleValue.webidl
index 3cd075b67e8..a87c2b29910 100644
--- a/components/script/dom/webidls/CSSStyleValue.webidl
+++ b/components/script/dom/webidls/CSSStyleValue.webidl
@@ -4,7 +4,7 @@
 
 // https://drafts.css-houdini.org/css-typed-om-1/#cssstylevalue
 // NOTE: should this be exposed to Window?
-[Pref="dom.worklet.enabled", Exposed=(Worklet)]
+[Pref="dom_worklet_enabled", Exposed=(Worklet)]
 interface CSSStyleValue {
     stringifier;
 };
diff --git a/components/script/dom/webidls/CanvasRenderingContext2D.webidl b/components/script/dom/webidls/CanvasRenderingContext2D.webidl
index 0a7dbf6ab94..4479d068186 100644
--- a/components/script/dom/webidls/CanvasRenderingContext2D.webidl
+++ b/components/script/dom/webidls/CanvasRenderingContext2D.webidl
@@ -139,12 +139,12 @@ interface mixin CanvasUserInterface {
 
 interface mixin CanvasText {
   // text (see also the CanvasPathDrawingStyles and CanvasTextDrawingStyles interfaces)
-  [Pref="dom.canvas_text.enabled"]
+  [Pref="dom_canvas_text_enabled"]
   undefined fillText(DOMString text, unrestricted double x, unrestricted double y,
                 optional unrestricted double maxWidth);
   //void strokeText(DOMString text, unrestricted double x, unrestricted double y,
   //                optional unrestricted double maxWidth);
-  [Pref="dom.canvas_text.enabled"]
+  [Pref="dom_canvas_text_enabled"]
   TextMetrics measureText(DOMString text);
 };
 
diff --git a/components/script/dom/webidls/Client.webidl b/components/script/dom/webidls/Client.webidl
index f5a9dee934e..f2b144ffa07 100644
--- a/components/script/dom/webidls/Client.webidl
+++ b/components/script/dom/webidls/Client.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/ServiceWorker/#client
 
-[Pref="dom.serviceworker.enabled", Exposed=ServiceWorker]
+[Pref="dom_serviceworker_enabled", Exposed=ServiceWorker]
 interface Client {
   readonly attribute USVString url;
   readonly attribute FrameType frameType;
diff --git a/components/script/dom/webidls/CompositionEvent.webidl b/components/script/dom/webidls/CompositionEvent.webidl
index 1ed323d26b3..3eeba65e29a 100644
--- a/components/script/dom/webidls/CompositionEvent.webidl
+++ b/components/script/dom/webidls/CompositionEvent.webidl
@@ -8,7 +8,7 @@
  */
 
 // https://w3c.github.io/uievents/#idl-compositionevent
-[Exposed=Window, Pref="dom.composition_event.enabled"]
+[Exposed=Window, Pref="dom_composition_event_enabled"]
 interface CompositionEvent : UIEvent {
   [Throws] constructor(DOMString type, optional CompositionEventInit eventInitDict = {});
   readonly attribute DOMString data;
diff --git a/components/script/dom/webidls/Crypto.webidl b/components/script/dom/webidls/Crypto.webidl
index 828273f4afa..cdda53e27ac 100644
--- a/components/script/dom/webidls/Crypto.webidl
+++ b/components/script/dom/webidls/Crypto.webidl
@@ -13,7 +13,7 @@ partial interface mixin WindowOrWorkerGlobalScope {
 
 [Exposed=(Window,Worker)]
 interface Crypto {
-  [SecureContext, Pref="dom.crypto.subtle.enabled"] readonly attribute SubtleCrypto subtle;
+  [SecureContext, Pref="dom_crypto_subtle_enabled"] readonly attribute SubtleCrypto subtle;
   [Throws] ArrayBufferView getRandomValues(ArrayBufferView array);
   [SecureContext] DOMString randomUUID();
 };
diff --git a/components/script/dom/webidls/CryptoKey.webidl b/components/script/dom/webidls/CryptoKey.webidl
index 1cad0097df2..4387ef75d98 100644
--- a/components/script/dom/webidls/CryptoKey.webidl
+++ b/components/script/dom/webidls/CryptoKey.webidl
@@ -8,7 +8,7 @@ enum KeyType { "public", "private", "secret" };
 
 enum KeyUsage { "encrypt", "decrypt", "sign", "verify", "deriveKey", "deriveBits", "wrapKey", "unwrapKey" };
 
-[SecureContext, Exposed=(Window,Worker), Serializable, Pref="dom.crypto.subtle.enabled"]
+[SecureContext, Exposed=(Window,Worker), Serializable, Pref="dom_crypto_subtle_enabled"]
 interface CryptoKey {
   readonly attribute KeyType type;
   readonly attribute boolean extractable;
diff --git a/components/script/dom/webidls/CustomElementRegistry.webidl b/components/script/dom/webidls/CustomElementRegistry.webidl
index be3d19b1cdd..818e8892461 100644
--- a/components/script/dom/webidls/CustomElementRegistry.webidl
+++ b/components/script/dom/webidls/CustomElementRegistry.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://html.spec.whatwg.org/multipage/#customelementregistry
-[Exposed=Window, Pref="dom.custom_elements.enabled"]
+[Exposed=Window, Pref="dom_customelements_enabled"]
 interface CustomElementRegistry {
   [Throws, CEReactions]
   undefined define(
diff --git a/components/script/dom/webidls/Element.webidl b/components/script/dom/webidls/Element.webidl
index 1a99d5ec480..c7884925541 100644
--- a/components/script/dom/webidls/Element.webidl
+++ b/components/script/dom/webidls/Element.webidl
@@ -83,7 +83,7 @@ interface Element : Node {
   [CEReactions, Throws]
   undefined insertAdjacentHTML(DOMString position, DOMString html);
 
-  [Throws, Pref="dom.shadowdom.enabled"] ShadowRoot attachShadow(ShadowRootInit init);
+  [Throws, Pref="dom_shadowdom_enabled"] ShadowRoot attachShadow(ShadowRootInit init);
   readonly attribute ShadowRoot? shadowRoot;
 };
 
diff --git a/components/script/dom/webidls/ExtendableEvent.webidl b/components/script/dom/webidls/ExtendableEvent.webidl
index 0b030873fc5..cf8a42169a0 100644
--- a/components/script/dom/webidls/ExtendableEvent.webidl
+++ b/components/script/dom/webidls/ExtendableEvent.webidl
@@ -5,7 +5,7 @@
 // https://w3c.github.io/ServiceWorker/#extendable-event
 
 [Exposed=ServiceWorker,
- Pref="dom.serviceworker.enabled"]
+ Pref="dom_serviceworker_enabled"]
 interface ExtendableEvent : Event {
   [Throws] constructor(DOMString type,
  optional ExtendableEventInit eventInitDict = {});
diff --git a/components/script/dom/webidls/ExtendableMessageEvent.webidl b/components/script/dom/webidls/ExtendableMessageEvent.webidl
index 247c08e7989..66fbb46371e 100644
--- a/components/script/dom/webidls/ExtendableMessageEvent.webidl
+++ b/components/script/dom/webidls/ExtendableMessageEvent.webidl
@@ -5,7 +5,7 @@
 // https://w3c.github.io/ServiceWorker/#extendablemessage-event-section
 
 [Exposed=ServiceWorker,
- Pref="dom.serviceworker.enabled"]
+ Pref="dom_serviceworker_enabled"]
 interface ExtendableMessageEvent : ExtendableEvent {
   [Throws] constructor(DOMString type, optional ExtendableMessageEventInit eventInitDict = {});
   readonly attribute any data;
diff --git a/components/script/dom/webidls/FakeXRDevice.webidl b/components/script/dom/webidls/FakeXRDevice.webidl
index 22a2ddbbd27..dd0bb24b8a4 100644
--- a/components/script/dom/webidls/FakeXRDevice.webidl
+++ b/components/script/dom/webidls/FakeXRDevice.webidl
@@ -6,7 +6,7 @@
 
 // https://github.com/immersive-web/webxr-test-api/
 
-[Exposed=Window, Pref="dom.webxr.test"]
+[Exposed=Window, Pref="dom_webxr_test"]
 interface FakeXRDevice {
   // Sets the values to be used for subsequent requestAnimationFrame() callbacks.
   [Throws] undefined setViews(sequence<FakeXRViewInit> views, optional sequence<FakeXRViewInit> secondaryViews);
diff --git a/components/script/dom/webidls/FakeXRInputController.webidl b/components/script/dom/webidls/FakeXRInputController.webidl
index 42230c980bb..25237f54c7d 100644
--- a/components/script/dom/webidls/FakeXRInputController.webidl
+++ b/components/script/dom/webidls/FakeXRInputController.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr-test-api/#fakexrinputcontroller
 
-[Exposed=Window, Pref="dom.webxr.test"]
+[Exposed=Window, Pref="dom_webxr_test"]
 interface FakeXRInputController {
   undefined setHandedness(XRHandedness handedness);
   undefined setTargetRayMode(XRTargetRayMode targetRayMode);
diff --git a/components/script/dom/webidls/GPUCanvasContext.webidl b/components/script/dom/webidls/GPUCanvasContext.webidl
index b85bb3c9bdf..e83421fa5ea 100644
--- a/components/script/dom/webidls/GPUCanvasContext.webidl
+++ b/components/script/dom/webidls/GPUCanvasContext.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://html.spec.whatwg.org/multipage/#htmlcanvaselement
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUCanvasContext {
     readonly attribute (HTMLCanvasElement or OffscreenCanvas) canvas;
 };
diff --git a/components/script/dom/webidls/Gamepad.webidl b/components/script/dom/webidls/Gamepad.webidl
index d716f0c0bc4..bef601c5c7c 100644
--- a/components/script/dom/webidls/Gamepad.webidl
+++ b/components/script/dom/webidls/Gamepad.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/gamepad/#gamepad-interface
-[Exposed=Window, Pref="dom.gamepad.enabled"]
+[Exposed=Window, Pref="dom_gamepad_enabled"]
 interface Gamepad {
     readonly attribute DOMString id;
     readonly attribute long index;
diff --git a/components/script/dom/webidls/GamepadButton.webidl b/components/script/dom/webidls/GamepadButton.webidl
index 748d47232ac..d4aa41be8d9 100644
--- a/components/script/dom/webidls/GamepadButton.webidl
+++ b/components/script/dom/webidls/GamepadButton.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/gamepad/#gamepadbutton-interface
-[Exposed=Window, Pref="dom.gamepad.enabled"]
+[Exposed=Window, Pref="dom_gamepad_enabled"]
 interface GamepadButton {
     readonly attribute boolean pressed;
     readonly attribute boolean touched;
diff --git a/components/script/dom/webidls/GamepadButtonList.webidl b/components/script/dom/webidls/GamepadButtonList.webidl
index 34ea9857071..24a82a4b322 100644
--- a/components/script/dom/webidls/GamepadButtonList.webidl
+++ b/components/script/dom/webidls/GamepadButtonList.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/gamepad/#dom-gamepad-buttons
-[Exposed=Window, Pref="dom.gamepad.enabled"]
+[Exposed=Window, Pref="dom_gamepad_enabled"]
 interface GamepadButtonList {
   getter GamepadButton? item(unsigned long index);
   readonly attribute unsigned long length;
diff --git a/components/script/dom/webidls/GamepadEvent.webidl b/components/script/dom/webidls/GamepadEvent.webidl
index 0da800bafe2..0dc82e4083b 100644
--- a/components/script/dom/webidls/GamepadEvent.webidl
+++ b/components/script/dom/webidls/GamepadEvent.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/gamepad/#gamepadevent-interface
-[Exposed=Window, Pref="dom.gamepad.enabled"]
+[Exposed=Window, Pref="dom_gamepad_enabled"]
 interface GamepadEvent : Event {
   [Throws] constructor(DOMString type, GamepadEventInit eventInitDict);
   readonly attribute Gamepad gamepad;
diff --git a/components/script/dom/webidls/GamepadHapticActuator.webidl b/components/script/dom/webidls/GamepadHapticActuator.webidl
index 1961da4c541..db6f6eb5f8b 100644
--- a/components/script/dom/webidls/GamepadHapticActuator.webidl
+++ b/components/script/dom/webidls/GamepadHapticActuator.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/gamepad/#gamepadhapticactuator-interface
-[Exposed=Window, Pref="dom.gamepad.enabled"]
+[Exposed=Window, Pref="dom_gamepad_enabled"]
 interface GamepadHapticActuator {
   /* [SameObject] */ readonly attribute /* FrozenArray<GamepadHapticEffectType> */ any effects;
   [NewObject]
diff --git a/components/script/dom/webidls/GamepadPose.webidl b/components/script/dom/webidls/GamepadPose.webidl
index 5afa9f3251e..aeb5411b12b 100644
--- a/components/script/dom/webidls/GamepadPose.webidl
+++ b/components/script/dom/webidls/GamepadPose.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/gamepad/extensions.html#gamepadpose-interface
-[Exposed=Window, Pref="dom.gamepad.enabled"]
+[Exposed=Window, Pref="dom_gamepad_enabled"]
 interface GamepadPose {
   readonly attribute boolean hasOrientation;
   readonly attribute boolean hasPosition;
diff --git a/components/script/dom/webidls/HTMLCanvasElement.webidl b/components/script/dom/webidls/HTMLCanvasElement.webidl
index cbcb6b4d030..2e7be0389be 100644
--- a/components/script/dom/webidls/HTMLCanvasElement.webidl
+++ b/components/script/dom/webidls/HTMLCanvasElement.webidl
@@ -29,7 +29,7 @@ interface HTMLCanvasElement : HTMLElement {
 };
 
 partial interface HTMLCanvasElement {
-    [Pref="dom.canvas_capture.enabled"]
+    [Pref="dom_canvas_capture_enabled"]
     MediaStream captureStream (optional double frameRequestRate);
 };
 
diff --git a/components/script/dom/webidls/HTMLElement.webidl b/components/script/dom/webidls/HTMLElement.webidl
index a67a13d4be4..76bfada1b94 100644
--- a/components/script/dom/webidls/HTMLElement.webidl
+++ b/components/script/dom/webidls/HTMLElement.webidl
@@ -24,9 +24,9 @@ interface HTMLElement : Element {
   //         attribute DOMString itemId;
   //readonly attribute HTMLPropertiesCollection properties;
   //         attribute any itemValue; // acts as DOMString on setting
-  [Pref="dom.microdata.testing.enabled"]
+  [Pref="dom_microdata_testing_enabled"]
   sequence<DOMString>? propertyNames();
-  [Pref="dom.microdata.testing.enabled"]
+  [Pref="dom_microdata_testing_enabled"]
   sequence<DOMString>? itemtypes();
 
   // user interaction
diff --git a/components/script/dom/webidls/HTMLInputElement.webidl b/components/script/dom/webidls/HTMLInputElement.webidl
index 519198cebd9..724f2cff9b5 100644
--- a/components/script/dom/webidls/HTMLInputElement.webidl
+++ b/components/script/dom/webidls/HTMLInputElement.webidl
@@ -109,7 +109,7 @@ interface HTMLInputElement : HTMLElement {
   // also has obsolete members
 
   // Select with file-system paths for testing purpose
-  [Pref="dom.testing.htmlinputelement.select_files.enabled"]
+  [Pref="dom_testing_html_input_element_select_files_enabled"]
   undefined selectFiles(sequence<DOMString> path);
 };
 
diff --git a/components/script/dom/webidls/HTMLVideoElement.webidl b/components/script/dom/webidls/HTMLVideoElement.webidl
index d9e6b86e4bb..f4550e9857b 100644
--- a/components/script/dom/webidls/HTMLVideoElement.webidl
+++ b/components/script/dom/webidls/HTMLVideoElement.webidl
@@ -17,6 +17,6 @@ interface HTMLVideoElement : HTMLMediaElement {
 };
 
 partial interface HTMLVideoElement {
-  [Pref="media.testing.enabled"]
+  [Pref="media_testing_enabled"]
   attribute EventHandler onpostershown;
 };
diff --git a/components/script/dom/webidls/ImageBitmap.webidl b/components/script/dom/webidls/ImageBitmap.webidl
index e2ace645e74..aaa35c67995 100644
--- a/components/script/dom/webidls/ImageBitmap.webidl
+++ b/components/script/dom/webidls/ImageBitmap.webidl
@@ -10,7 +10,7 @@
  */
 
 //[Exposed=(Window,Worker), Serializable, Transferable]
-[Exposed=(Window,Worker), Pref="dom.imagebitmap.enabled"]
+[Exposed=(Window,Worker), Pref="dom_imagebitmap_enabled"]
 interface ImageBitmap {
   readonly attribute unsigned long width;
   readonly attribute unsigned long height;
diff --git a/components/script/dom/webidls/IntersectionObserver.webidl b/components/script/dom/webidls/IntersectionObserver.webidl
index dc24a856363..9607864408e 100644
--- a/components/script/dom/webidls/IntersectionObserver.webidl
+++ b/components/script/dom/webidls/IntersectionObserver.webidl
@@ -16,7 +16,7 @@ dictionary IntersectionObserverInit {
   boolean trackVisibility = false;
 };
 
-[Pref="dom.intersection_observer.enabled", Exposed=(Window)]
+[Pref="dom_intersection_observer_enabled", Exposed=(Window)]
 interface IntersectionObserver {
   constructor(IntersectionObserverCallback callback, optional IntersectionObserverInit options = {});
   readonly attribute (Element or Document)? root;
diff --git a/components/script/dom/webidls/IntersectionObserverEntry.webidl b/components/script/dom/webidls/IntersectionObserverEntry.webidl
index 108ad6636de..5e9423a965c 100644
--- a/components/script/dom/webidls/IntersectionObserverEntry.webidl
+++ b/components/script/dom/webidls/IntersectionObserverEntry.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/IntersectionObserver/#intersection-observer-entry
 
-[Pref="dom.intersection_observer.enabled", Exposed=(Window)]
+[Pref="dom_intersection_observer_enabled", Exposed=(Window)]
 interface IntersectionObserverEntry {
   constructor(IntersectionObserverEntryInit intersectionObserverEntryInit);
   readonly attribute DOMHighResTimeStamp time;
diff --git a/components/script/dom/webidls/MediaDeviceInfo.webidl b/components/script/dom/webidls/MediaDeviceInfo.webidl
index ab24f8046f9..d6caaa43499 100644
--- a/components/script/dom/webidls/MediaDeviceInfo.webidl
+++ b/components/script/dom/webidls/MediaDeviceInfo.webidl
@@ -5,7 +5,7 @@
  // https://w3c.github.io/mediacapture-main/#device-info
 
 [Exposed=Window,
-SecureContext, Pref="dom.webrtc.enabled"]
+SecureContext, Pref="dom_webrtc_enabled"]
 interface MediaDeviceInfo {
   readonly attribute DOMString deviceId;
   readonly attribute MediaDeviceKind kind;
diff --git a/components/script/dom/webidls/MediaDevices.webidl b/components/script/dom/webidls/MediaDevices.webidl
index 53e6c3599a4..8d14e60abb5 100644
--- a/components/script/dom/webidls/MediaDevices.webidl
+++ b/components/script/dom/webidls/MediaDevices.webidl
@@ -5,7 +5,7 @@
 // https://w3c.github.io/mediacapture-main/#dom-mediadevices
 
 [Exposed=Window,
-SecureContext, Pref="dom.webrtc.enabled"]
+SecureContext, Pref="dom_webrtc_enabled"]
 interface MediaDevices : EventTarget {
     //                attribute EventHandler ondevicechange;
     Promise<sequence<MediaDeviceInfo>> enumerateDevices();
@@ -13,7 +13,7 @@ interface MediaDevices : EventTarget {
 
 partial interface Navigator {
     // [SameObject, SecureContext]
-    [Pref="dom.webrtc.enabled"] readonly        attribute MediaDevices mediaDevices;
+    [Pref="dom_webrtc_enabled"] readonly        attribute MediaDevices mediaDevices;
 };
 
 partial interface MediaDevices {
diff --git a/components/script/dom/webidls/MouseEvent.webidl b/components/script/dom/webidls/MouseEvent.webidl
index ba717f724a4..0a3c5c015fd 100644
--- a/components/script/dom/webidls/MouseEvent.webidl
+++ b/components/script/dom/webidls/MouseEvent.webidl
@@ -26,7 +26,7 @@ interface MouseEvent : UIEvent {
     readonly    attribute unsigned short buttons;
     //boolean getModifierState (DOMString keyArg);
 
-    [Pref="dom.mouseevent.which.enabled"]
+    [Pref="dom_mouse_event_which_enabled"]
     readonly    attribute long           which;
 };
 
diff --git a/components/script/dom/webidls/MutationObserver.webidl b/components/script/dom/webidls/MutationObserver.webidl
index baa9a1a79b0..4f643c7b222 100644
--- a/components/script/dom/webidls/MutationObserver.webidl
+++ b/components/script/dom/webidls/MutationObserver.webidl
@@ -7,7 +7,7 @@
  */
 
 // https://dom.spec.whatwg.org/#mutationobserver
-[Exposed=Window, Pref="dom.mutation_observer.enabled"]
+[Exposed=Window, Pref="dom_mutation_observer_enabled"]
 interface MutationObserver {
     [Throws] constructor(MutationCallback callback);
     [Throws]
diff --git a/components/script/dom/webidls/MutationRecord.webidl b/components/script/dom/webidls/MutationRecord.webidl
index 2c08fcea71f..edc5c9e8825 100644
--- a/components/script/dom/webidls/MutationRecord.webidl
+++ b/components/script/dom/webidls/MutationRecord.webidl
@@ -7,7 +7,7 @@
  */
 
 // https://dom.spec.whatwg.org/#mutationrecord
-[Pref="dom.mutation_observer.enabled", Exposed=Window]
+[Pref="dom_mutation_observer_enabled", Exposed=Window]
 interface MutationRecord {
     readonly attribute DOMString type;
     [SameObject]
diff --git a/components/script/dom/webidls/NavigationPreloadManager.webidl b/components/script/dom/webidls/NavigationPreloadManager.webidl
index 1c2e4d09189..026bcafea13 100644
--- a/components/script/dom/webidls/NavigationPreloadManager.webidl
+++ b/components/script/dom/webidls/NavigationPreloadManager.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/ServiceWorker/#navigation-preload-manager
-[Pref="dom.serviceworker.enabled", SecureContext, Exposed=(Window,Worker)]
+[Pref="dom_serviceworker_enabled", SecureContext, Exposed=(Window,Worker)]
 interface NavigationPreloadManager {
   Promise<undefined> enable();
   Promise<undefined> disable();
diff --git a/components/script/dom/webidls/Navigator.webidl b/components/script/dom/webidls/Navigator.webidl
index 2fcef010b4a..05fbdf62024 100644
--- a/components/script/dom/webidls/Navigator.webidl
+++ b/components/script/dom/webidls/Navigator.webidl
@@ -33,12 +33,12 @@ interface mixin NavigatorID {
 
 // https://webbluetoothcg.github.io/web-bluetooth/#navigator-extensions
 partial interface Navigator {
-  [SameObject, Pref="dom.bluetooth.enabled"] readonly attribute Bluetooth bluetooth;
+  [SameObject, Pref="dom_bluetooth_enabled"] readonly attribute Bluetooth bluetooth;
 };
 
 // https://w3c.github.io/ServiceWorker/#navigator-service-worker
 partial interface Navigator {
-  [SameObject, Pref="dom.serviceworker.enabled"] readonly attribute ServiceWorkerContainer serviceWorker;
+  [SameObject, Pref="dom_serviceworker_enabled"] readonly attribute ServiceWorkerContainer serviceWorker;
 };
 
 // https://html.spec.whatwg.org/multipage/#navigatorlanguage
@@ -63,12 +63,12 @@ interface mixin NavigatorCookies {
 // https://w3c.github.io/permissions/#navigator-and-workernavigator-extension
 [Exposed=(Window)]
 partial interface Navigator {
-  [Pref="dom.permissions.enabled"] readonly attribute Permissions permissions;
+  [Pref="dom_permissions_enabled"] readonly attribute Permissions permissions;
 };
 
 // https://w3c.github.io/gamepad/#navigator-interface-extension
 partial interface Navigator {
-  [Pref="dom.gamepad.enabled"] sequence<Gamepad?> getGamepads();
+  [Pref="dom_gamepad_enabled"] sequence<Gamepad?> getGamepads();
 };
 
 // https://html.spec.whatwg.org/multipage/#navigatorconcurrenthardware
diff --git a/components/script/dom/webidls/OffscreenCanvas.webidl b/components/script/dom/webidls/OffscreenCanvas.webidl
index 04c28f989a5..cc19cefa868 100644
--- a/components/script/dom/webidls/OffscreenCanvas.webidl
+++ b/components/script/dom/webidls/OffscreenCanvas.webidl
@@ -13,7 +13,7 @@ dictionary ImageEncodeOptions {
 
 //enum OffscreenRenderingContextId { "2d", "webgl", "webgl2" };
 
-[Exposed=(Window,Worker)/*, Transferable*/, Pref="dom.offscreen_canvas.enabled"]
+[Exposed=(Window,Worker)/*, Transferable*/, Pref="dom_offscreen_canvas_enabled"]
 interface OffscreenCanvas : EventTarget {
   [Throws] constructor([EnforceRange] unsigned long long width, [EnforceRange] unsigned long long height);
   attribute [EnforceRange] unsigned long long width;
diff --git a/components/script/dom/webidls/OffscreenCanvasRenderingContext2D.webidl b/components/script/dom/webidls/OffscreenCanvasRenderingContext2D.webidl
index c129bfa8e47..5d6aef5e014 100644
--- a/components/script/dom/webidls/OffscreenCanvasRenderingContext2D.webidl
+++ b/components/script/dom/webidls/OffscreenCanvasRenderingContext2D.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://html.spec.whatwg.org/multipage/#the-offscreen-2d-rendering-context
-[Exposed=(Window,Worker), Pref="dom.offscreen_canvas.enabled"]
+[Exposed=(Window,Worker), Pref="dom_offscreen_canvas_enabled"]
 interface OffscreenCanvasRenderingContext2D {
   //void commit();
   readonly attribute OffscreenCanvas canvas;
diff --git a/components/script/dom/webidls/PaintRenderingContext2D.webidl b/components/script/dom/webidls/PaintRenderingContext2D.webidl
index bc415450358..8361c298866 100644
--- a/components/script/dom/webidls/PaintRenderingContext2D.webidl
+++ b/components/script/dom/webidls/PaintRenderingContext2D.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://drafts.css-houdini.org/css-paint-api/#paintrenderingcontext2d
-[Pref="dom.worklet.enabled", Exposed=PaintWorklet]
+[Pref="dom_worklet_enabled", Exposed=PaintWorklet]
 interface PaintRenderingContext2D {
 };
 PaintRenderingContext2D includes CanvasState;
diff --git a/components/script/dom/webidls/PaintSize.webidl b/components/script/dom/webidls/PaintSize.webidl
index ed1b46d29f4..2c3e669d32e 100644
--- a/components/script/dom/webidls/PaintSize.webidl
+++ b/components/script/dom/webidls/PaintSize.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://drafts.css-houdini.org/css-paint-api/#paintsize
-[Pref="dom.worklet.enabled", Exposed=PaintWorklet]
+[Pref="dom_worklet_enabled", Exposed=PaintWorklet]
 interface PaintSize {
     readonly attribute double width;
     readonly attribute double height;
diff --git a/components/script/dom/webidls/PaintWorkletGlobalScope.webidl b/components/script/dom/webidls/PaintWorkletGlobalScope.webidl
index 981df09321f..a5918c06616 100644
--- a/components/script/dom/webidls/PaintWorkletGlobalScope.webidl
+++ b/components/script/dom/webidls/PaintWorkletGlobalScope.webidl
@@ -3,11 +3,11 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://drafts.css-houdini.org/css-paint-api/#paintworkletglobalscope
-[Global=(Worklet,PaintWorklet), Pref="dom.worklet.enabled", Exposed=PaintWorklet]
+[Global=(Worklet,PaintWorklet), Pref="dom_worklet_enabled", Exposed=PaintWorklet]
 interface PaintWorkletGlobalScope : WorkletGlobalScope {
     [Throws] undefined registerPaint(DOMString name, VoidFunction paintCtor);
     // This function is to be used only for testing, and should not be
     // accessible outside of that use.
-    [Pref="dom.worklet.blockingsleep.enabled"]
+    [Pref="dom_worklet_blockingsleep_enabled"]
     undefined sleep(unsigned long long ms);
 };
diff --git a/components/script/dom/webidls/PerformanceNavigationTiming.webidl b/components/script/dom/webidls/PerformanceNavigationTiming.webidl
index 8bd657dbdfb..4757e7fd7d0 100644
--- a/components/script/dom/webidls/PerformanceNavigationTiming.webidl
+++ b/components/script/dom/webidls/PerformanceNavigationTiming.webidl
@@ -27,6 +27,6 @@ interface PerformanceNavigationTiming : PerformanceResourceTiming {
     readonly attribute unsigned short       redirectCount;
     [Default] object toJSON();
     /* Servo-only attribute for measuring when the top-level document (not iframes) is complete. */
-    [Pref="dom.testperf.enabled"]
+    [Pref="dom_testperf_enabled"]
     readonly attribute DOMHighResTimeStamp  topLevelDomComplete;
 };
diff --git a/components/script/dom/webidls/PermissionStatus.webidl b/components/script/dom/webidls/PermissionStatus.webidl
index 83c0371e0de..a5aebda20dd 100644
--- a/components/script/dom/webidls/PermissionStatus.webidl
+++ b/components/script/dom/webidls/PermissionStatus.webidl
@@ -28,7 +28,7 @@ enum PermissionName {
   "persistent-storage",
 };
 
-[Pref="dom.permissions.enabled", Exposed=(Window,Worker)]
+[Pref="dom_permissions_enabled", Exposed=(Window,Worker)]
 interface PermissionStatus : EventTarget {
   readonly attribute PermissionState state;
   attribute EventHandler onchange;
diff --git a/components/script/dom/webidls/Permissions.webidl b/components/script/dom/webidls/Permissions.webidl
index 5b4092cc645..21e20eb2bf5 100644
--- a/components/script/dom/webidls/Permissions.webidl
+++ b/components/script/dom/webidls/Permissions.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/permissions/#permissions-interface
 
-[Pref="dom.permissions.enabled", Exposed=(Window,Worker)]
+[Pref="dom_permissions_enabled", Exposed=(Window,Worker)]
 interface Permissions {
   Promise<PermissionStatus> query(object permissionDesc);
 
diff --git a/components/script/dom/webidls/RTCDataChannel.webidl b/components/script/dom/webidls/RTCDataChannel.webidl
index e67c299bcea..419b05bd3f9 100644
--- a/components/script/dom/webidls/RTCDataChannel.webidl
+++ b/components/script/dom/webidls/RTCDataChannel.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#dom-rtcdatachannel
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCDataChannel : EventTarget {
   readonly attribute USVString label;
   readonly attribute boolean ordered;
diff --git a/components/script/dom/webidls/RTCDataChannelEvent.webidl b/components/script/dom/webidls/RTCDataChannelEvent.webidl
index bc564a12138..5d2a8e6df24 100644
--- a/components/script/dom/webidls/RTCDataChannelEvent.webidl
+++ b/components/script/dom/webidls/RTCDataChannelEvent.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#dom-rtcdatachannelevent
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCDataChannelEvent : Event {
   constructor(DOMString type, RTCDataChannelEventInit eventInitDict);
   readonly attribute RTCDataChannel channel;
diff --git a/components/script/dom/webidls/RTCError.webidl b/components/script/dom/webidls/RTCError.webidl
index f7ffa3d2d57..a745cf5e77f 100644
--- a/components/script/dom/webidls/RTCError.webidl
+++ b/components/script/dom/webidls/RTCError.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#dom-rtcerror
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCError : DOMException {
   constructor(RTCErrorInit init, optional DOMString message = "");
   readonly attribute RTCErrorDetailType errorDetail;
diff --git a/components/script/dom/webidls/RTCErrorEvent.webidl b/components/script/dom/webidls/RTCErrorEvent.webidl
index d3ac256744c..c5b7c3e9cc8 100644
--- a/components/script/dom/webidls/RTCErrorEvent.webidl
+++ b/components/script/dom/webidls/RTCErrorEvent.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#dom-rtcerrorevent
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCErrorEvent : Event {
   constructor(DOMString type, RTCErrorEventInit eventInitDict);
   [SameObject] readonly attribute RTCError error;
diff --git a/components/script/dom/webidls/RTCIceCandidate.webidl b/components/script/dom/webidls/RTCIceCandidate.webidl
index fde0421c8c0..266fe353f37 100644
--- a/components/script/dom/webidls/RTCIceCandidate.webidl
+++ b/components/script/dom/webidls/RTCIceCandidate.webidl
@@ -5,7 +5,7 @@
 // https://w3c.github.io/webrtc-pc/#rtcicecandidate-interface
 
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCIceCandidate {
     [Throws] constructor(optional RTCIceCandidateInit candidateInitDict = {});
     readonly attribute DOMString               candidate;
diff --git a/components/script/dom/webidls/RTCPeerConnection.webidl b/components/script/dom/webidls/RTCPeerConnection.webidl
index 85a7297fce1..24ced7bcce6 100644
--- a/components/script/dom/webidls/RTCPeerConnection.webidl
+++ b/components/script/dom/webidls/RTCPeerConnection.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#interface-definition
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCPeerConnection : EventTarget {
     [Throws] constructor(optional RTCConfiguration configuration = {});
     Promise<RTCSessionDescriptionInit> createOffer(optional RTCOfferOptions options = {});
@@ -138,7 +138,7 @@ partial interface RTCPeerConnection {
     // RTCRtpSender                addTrack(MediaStreamTrack track,
     //                                      MediaStream... streams);
     // void                        removeTrack(RTCRtpSender sender);
-    [Pref="dom.webrtc.transceiver.enabled"]
+    [Pref="dom_webrtc_transceiver_enabled"]
     RTCRtpTransceiver           addTransceiver((MediaStreamTrack or DOMString) trackOrKind,
                                                optional RTCRtpTransceiverInit init = {});
     attribute EventHandler ontrack;
diff --git a/components/script/dom/webidls/RTCPeerConnectionIceEvent.webidl b/components/script/dom/webidls/RTCPeerConnectionIceEvent.webidl
index 2ffd69cea50..95094c45f3b 100644
--- a/components/script/dom/webidls/RTCPeerConnectionIceEvent.webidl
+++ b/components/script/dom/webidls/RTCPeerConnectionIceEvent.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#rtcpeerconnectioniceevent
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCPeerConnectionIceEvent : Event {
     [Throws] constructor(DOMString type, optional RTCPeerConnectionIceEventInit eventInitDict = {});
     readonly attribute RTCIceCandidate? candidate;
diff --git a/components/script/dom/webidls/RTCRtpSender.webidl b/components/script/dom/webidls/RTCRtpSender.webidl
index 752ab7682b8..938ca9e8a63 100644
--- a/components/script/dom/webidls/RTCRtpSender.webidl
+++ b/components/script/dom/webidls/RTCRtpSender.webidl
@@ -34,7 +34,7 @@ dictionary RTCRtpSendParameters : RTCRtpParameters {
   required sequence<RTCRtpEncodingParameters> encodings;
 };
 
-[Exposed=Window, Pref="dom.webrtc.transceiver.enabled"]
+[Exposed=Window, Pref="dom_webrtc_transceiver_enabled"]
 interface RTCRtpSender {
   //readonly attribute MediaStreamTrack? track;
   //readonly attribute RTCDtlsTransport? transport;
diff --git a/components/script/dom/webidls/RTCRtpTransceiver.webidl b/components/script/dom/webidls/RTCRtpTransceiver.webidl
index 408c2708709..f11b9853682 100644
--- a/components/script/dom/webidls/RTCRtpTransceiver.webidl
+++ b/components/script/dom/webidls/RTCRtpTransceiver.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#rtcrtptransceiver-interface
 
-[Exposed=Window, Pref="dom.webrtc.transceiver.enabled"]
+[Exposed=Window, Pref="dom_webrtc_transceiver_enabled"]
 interface RTCRtpTransceiver {
   //readonly attribute DOMString? mid;
   [SameObject] readonly attribute RTCRtpSender sender;
diff --git a/components/script/dom/webidls/RTCSessionDescription.webidl b/components/script/dom/webidls/RTCSessionDescription.webidl
index f13d0fd0d9f..0fb325eae41 100644
--- a/components/script/dom/webidls/RTCSessionDescription.webidl
+++ b/components/script/dom/webidls/RTCSessionDescription.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#rtcsessiondescription-class
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCSessionDescription {
     [Throws] constructor(RTCSessionDescriptionInit descriptionInitDict);
     readonly attribute RTCSdpType type;
diff --git a/components/script/dom/webidls/RTCTrackEvent.webidl b/components/script/dom/webidls/RTCTrackEvent.webidl
index c2283e5a803..c43b86710b4 100644
--- a/components/script/dom/webidls/RTCTrackEvent.webidl
+++ b/components/script/dom/webidls/RTCTrackEvent.webidl
@@ -4,7 +4,7 @@
 
 // https://w3c.github.io/webrtc-pc/#dom-rtctrackevent
 
-[Exposed=Window, Pref="dom.webrtc.enabled"]
+[Exposed=Window, Pref="dom_webrtc_enabled"]
 interface RTCTrackEvent : Event {
     [Throws] constructor(DOMString type, RTCTrackEventInit eventInitDict);
     // readonly attribute RTCRtpReceiver           receiver;
diff --git a/components/script/dom/webidls/ResizeObserver.webidl b/components/script/dom/webidls/ResizeObserver.webidl
index fc0a87589d5..2f3b9064477 100644
--- a/components/script/dom/webidls/ResizeObserver.webidl
+++ b/components/script/dom/webidls/ResizeObserver.webidl
@@ -4,7 +4,7 @@
 
 // https://drafts.csswg.org/resize-observer/#resize-observer-interface
 
-[Pref="dom.resize_observer.enabled", Exposed=(Window)]
+[Pref="dom_resize_observer_enabled", Exposed=(Window)]
 interface ResizeObserver {
     constructor(ResizeObserverCallback callback);
     undefined observe(Element target, optional ResizeObserverOptions options = {});
diff --git a/components/script/dom/webidls/ResizeObserverEntry.webidl b/components/script/dom/webidls/ResizeObserverEntry.webidl
index 8cb8802023a..0b7b5c2f5a9 100644
--- a/components/script/dom/webidls/ResizeObserverEntry.webidl
+++ b/components/script/dom/webidls/ResizeObserverEntry.webidl
@@ -4,7 +4,7 @@
 
  // https://drafts.csswg.org/resize-observer/#resize-observer-entry-interface
 
-[Pref="dom.resize_observer.enabled", Exposed=Window]
+[Pref="dom_resize_observer_enabled", Exposed=Window]
 interface ResizeObserverEntry {
     readonly attribute Element target;
     readonly attribute DOMRectReadOnly contentRect;
diff --git a/components/script/dom/webidls/ResizeObserverSize.webidl b/components/script/dom/webidls/ResizeObserverSize.webidl
index 5cc8db2dbcd..e4bcb1ace78 100644
--- a/components/script/dom/webidls/ResizeObserverSize.webidl
+++ b/components/script/dom/webidls/ResizeObserverSize.webidl
@@ -4,7 +4,7 @@
 
 // https://drafts.csswg.org/resize-observer/#resizeobserversize
 
-[Pref="dom.resize_observer.enabled", Exposed=Window]
+[Pref="dom_resize_observer_enabled", Exposed=Window]
 interface ResizeObserverSize {
     readonly attribute unrestricted double inlineSize;
     readonly attribute unrestricted double blockSize;
diff --git a/components/script/dom/webidls/SVGElement.webidl b/components/script/dom/webidls/SVGElement.webidl
index e826c741e66..e6bc468d5dc 100644
--- a/components/script/dom/webidls/SVGElement.webidl
+++ b/components/script/dom/webidls/SVGElement.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://svgwg.org/svg2-draft/types.html#InterfaceSVGElement
-[Exposed=Window, Pref="dom.svg.enabled"]
+[Exposed=Window, Pref="dom_svg_enabled"]
 interface SVGElement : Element {
 
   //[SameObject] readonly attribute SVGAnimatedString className;
diff --git a/components/script/dom/webidls/SVGGraphicsElement.webidl b/components/script/dom/webidls/SVGGraphicsElement.webidl
index 052182e374d..ab08503e7ef 100644
--- a/components/script/dom/webidls/SVGGraphicsElement.webidl
+++ b/components/script/dom/webidls/SVGGraphicsElement.webidl
@@ -10,7 +10,7 @@
 //  boolean clipped = false;
 //};
 
-[Exposed=Window, Abstract, Pref="dom.svg.enabled"]
+[Exposed=Window, Abstract, Pref="dom_svg_enabled"]
 interface SVGGraphicsElement : SVGElement {
   //[SameObject] readonly attribute SVGAnimatedTransformList transform;
 
diff --git a/components/script/dom/webidls/SVGSVGElement.webidl b/components/script/dom/webidls/SVGSVGElement.webidl
index 0e61776a40e..25b390cf15a 100644
--- a/components/script/dom/webidls/SVGSVGElement.webidl
+++ b/components/script/dom/webidls/SVGSVGElement.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://svgwg.org/svg2-draft/struct.html#InterfaceSVGSVGElement
-[Exposed=Window, Pref="dom.svg.enabled"]
+[Exposed=Window, Pref="dom_svg_enabled"]
 interface SVGSVGElement : SVGGraphicsElement {
 
   //[SameObject] readonly attribute SVGAnimatedLength x;
diff --git a/components/script/dom/webidls/ServiceWorker.webidl b/components/script/dom/webidls/ServiceWorker.webidl
index a5bc8938602..ee12c92b6e2 100644
--- a/components/script/dom/webidls/ServiceWorker.webidl
+++ b/components/script/dom/webidls/ServiceWorker.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/ServiceWorker/#serviceworker-interface
-[Pref="dom.serviceworker.enabled", SecureContext, Exposed=(Window,Worker)]
+[Pref="dom_serviceworker_enabled", SecureContext, Exposed=(Window,Worker)]
 interface ServiceWorker : EventTarget {
   readonly attribute USVString scriptURL;
   readonly attribute ServiceWorkerState state;
diff --git a/components/script/dom/webidls/ServiceWorkerContainer.webidl b/components/script/dom/webidls/ServiceWorkerContainer.webidl
index 18deb5e58f4..540079583b9 100644
--- a/components/script/dom/webidls/ServiceWorkerContainer.webidl
+++ b/components/script/dom/webidls/ServiceWorkerContainer.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/ServiceWorker/#serviceworkercontainer-interface
-[Pref="dom.serviceworker.enabled", Exposed=(Window,Worker)]
+[Pref="dom_serviceworker_enabled", Exposed=(Window,Worker)]
 interface ServiceWorkerContainer : EventTarget {
   readonly attribute ServiceWorker? controller;
   //readonly attribute Promise<ServiceWorkerRegistration> ready;
diff --git a/components/script/dom/webidls/ServiceWorkerGlobalScope.webidl b/components/script/dom/webidls/ServiceWorkerGlobalScope.webidl
index 257f3ff3252..f7535867deb 100644
--- a/components/script/dom/webidls/ServiceWorkerGlobalScope.webidl
+++ b/components/script/dom/webidls/ServiceWorkerGlobalScope.webidl
@@ -5,7 +5,7 @@
 // https://w3c.github.io/ServiceWorker/#serviceworkerglobalscope
 
 [Global=(Worker,ServiceWorker), Exposed=ServiceWorker,
- Pref="dom.serviceworker.enabled"]
+ Pref="dom_serviceworker_enabled"]
 interface ServiceWorkerGlobalScope : WorkerGlobalScope {
   // A container for a list of Client objects that correspond to
   // browsing contexts (or shared workers) that are on the origin of this SW
diff --git a/components/script/dom/webidls/ServiceWorkerRegistration.webidl b/components/script/dom/webidls/ServiceWorkerRegistration.webidl
index f7a10659513..29982ee8ec3 100644
--- a/components/script/dom/webidls/ServiceWorkerRegistration.webidl
+++ b/components/script/dom/webidls/ServiceWorkerRegistration.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://w3c.github.io/ServiceWorker/#serviceworkerregistration-interface
-[Pref="dom.serviceworker.enabled", SecureContext, Exposed=(Window,Worker)]
+[Pref="dom_serviceworker_enabled", SecureContext, Exposed=(Window,Worker)]
 interface ServiceWorkerRegistration : EventTarget {
   readonly attribute ServiceWorker? installing;
   readonly attribute ServiceWorker? waiting;
diff --git a/components/script/dom/webidls/StylePropertyMapReadOnly.webidl b/components/script/dom/webidls/StylePropertyMapReadOnly.webidl
index 7f3860ee701..b427ebd7ba0 100644
--- a/components/script/dom/webidls/StylePropertyMapReadOnly.webidl
+++ b/components/script/dom/webidls/StylePropertyMapReadOnly.webidl
@@ -4,7 +4,7 @@
 
 // https://drafts.css-houdini.org/css-typed-om-1/#stylepropertymapreadonly
 // NOTE: should this be exposed to Window?
-[Pref="dom.worklet.enabled", Exposed=(Worklet)]
+[Pref="dom_worklet_enabled", Exposed=(Worklet)]
 interface StylePropertyMapReadOnly {
     CSSStyleValue? get(DOMString property);
     // sequence<CSSStyleValue> getAll(DOMString property);
diff --git a/components/script/dom/webidls/SubtleCrypto.webidl b/components/script/dom/webidls/SubtleCrypto.webidl
index be01cebf589..e0bc1bc04a5 100644
--- a/components/script/dom/webidls/SubtleCrypto.webidl
+++ b/components/script/dom/webidls/SubtleCrypto.webidl
@@ -18,7 +18,7 @@ dictionary KeyAlgorithm {
 
 enum KeyFormat { "raw", "spki", "pkcs8", "jwk" };
 
-[SecureContext,Exposed=(Window,Worker),Pref="dom.crypto.subtle.enabled"]
+[SecureContext,Exposed=(Window,Worker),Pref="dom_crypto_subtle_enabled"]
 interface SubtleCrypto {
   Promise<any> encrypt(AlgorithmIdentifier algorithm,
                        CryptoKey key,
diff --git a/components/script/dom/webidls/TestBinding.webidl b/components/script/dom/webidls/TestBinding.webidl
index bd6cb2432a4..ee13ed57d55 100644
--- a/components/script/dom/webidls/TestBinding.webidl
+++ b/components/script/dom/webidls/TestBinding.webidl
@@ -100,7 +100,7 @@ dictionary TestURLLike {
   required DOMString href;
 };
 
-[Pref="dom.testbinding.enabled",
+[Pref="dom_testbinding_enabled",
  Exposed=(Window,Worker)
 ]
 interface TestBinding {
@@ -516,28 +516,28 @@ interface TestBinding {
   boolean BooleanMozPreference(DOMString pref_name);
   DOMString StringMozPreference(DOMString pref_name);
 
-  [Pref="dom.testbinding.prefcontrolled.enabled"]
+  [Pref="dom_testbinding_prefcontrolled_enabled"]
   readonly attribute boolean prefControlledAttributeDisabled;
-  [Pref="dom.testbinding.prefcontrolled.enabled"]
+  [Pref="dom_testbinding_prefcontrolled_enabled"]
   static readonly attribute boolean prefControlledStaticAttributeDisabled;
-  [Pref="dom.testbinding.prefcontrolled.enabled"]
+  [Pref="dom_testbinding_prefcontrolled_enabled"]
   undefined prefControlledMethodDisabled();
-  [Pref="dom.testbinding.prefcontrolled.enabled"]
+  [Pref="dom_testbinding_prefcontrolled_enabled"]
   static undefined prefControlledStaticMethodDisabled();
-  [Pref="dom.testbinding.prefcontrolled.enabled"]
+  [Pref="dom_testbinding_prefcontrolled_enabled"]
   const unsigned short prefControlledConstDisabled = 0;
-  [Pref="layout.animations.test.enabled"]
+  [Pref="layout_animations_test_enabled"]
   undefined advanceClock(long millis);
 
-  [Pref="dom.testbinding.prefcontrolled2.enabled"]
+  [Pref="dom_testbinding_prefcontrolled2_enabled"]
   readonly attribute boolean prefControlledAttributeEnabled;
-  [Pref="dom.testbinding.prefcontrolled2.enabled"]
+  [Pref="dom_testbinding_prefcontrolled2_enabled"]
   static readonly attribute boolean prefControlledStaticAttributeEnabled;
-  [Pref="dom.testbinding.prefcontrolled2.enabled"]
+  [Pref="dom_testbinding_prefcontrolled2_enabled"]
   undefined prefControlledMethodEnabled();
-  [Pref="dom.testbinding.prefcontrolled2.enabled"]
+  [Pref="dom_testbinding_prefcontrolled2_enabled"]
   static undefined prefControlledStaticMethodEnabled();
-  [Pref="dom.testbinding.prefcontrolled2.enabled"]
+  [Pref="dom_testbinding_prefcontrolled2_enabled"]
   const unsigned short prefControlledConstEnabled = 0;
 
   [Func="TestBinding::condition_unsatisfied"]
@@ -609,11 +609,11 @@ callback SimpleCallback = undefined(any value);
 callback callbackWithOnlyOneOptionalArg = Promise<undefined> (optional any reason);
 
 partial interface TestBinding {
-  [Pref="dom.testable_crash.enabled"]
+  [Pref="dom_testable_crash_enabled"]
   undefined crashHard();
 };
 
-[Exposed=(Window,Worker), Pref="dom.testbinding.enabled"]
+[Exposed=(Window,Worker), Pref="dom_testbinding_enabled"]
 namespace TestNS {
     const unsigned long ONE   = 1;
     const unsigned long TWO   = 0x2;
diff --git a/components/script/dom/webidls/TestBindingIterable.webidl b/components/script/dom/webidls/TestBindingIterable.webidl
index 46a2d319e3d..cc7628af707 100644
--- a/components/script/dom/webidls/TestBindingIterable.webidl
+++ b/components/script/dom/webidls/TestBindingIterable.webidl
@@ -5,7 +5,7 @@
 // This interface is entirely internal to Servo, and should not be accessible to
 // web pages.
 
-[Pref="dom.testbinding.enabled", Exposed=(Window,Worker)]
+[Pref="dom_testbinding_enabled", Exposed=(Window,Worker)]
 interface TestBindingIterable {
   [Throws] constructor();
   undefined add(DOMString arg);
diff --git a/components/script/dom/webidls/TestBindingMaplike.webidl b/components/script/dom/webidls/TestBindingMaplike.webidl
index f9712d63a8a..8debb804a3e 100644
--- a/components/script/dom/webidls/TestBindingMaplike.webidl
+++ b/components/script/dom/webidls/TestBindingMaplike.webidl
@@ -5,7 +5,7 @@
 // This interface is entirely internal to Servo, and should not be accessible to
 // web pages.
 
-[Pref="dom.testbinding.enabled", Exposed=(Window,Worker)]
+[Pref="dom_testbinding_enabled", Exposed=(Window,Worker)]
 interface TestBindingMaplike {
   [Throws]
   constructor();
diff --git a/components/script/dom/webidls/TestBindingPairIterable.webidl b/components/script/dom/webidls/TestBindingPairIterable.webidl
index 64499e7464c..e3106949e3e 100644
--- a/components/script/dom/webidls/TestBindingPairIterable.webidl
+++ b/components/script/dom/webidls/TestBindingPairIterable.webidl
@@ -5,7 +5,7 @@
 // This interface is entirely internal to Servo, and should not be accessible to
 // web pages.
 
-[Pref="dom.testbinding.enabled", Exposed=(Window,Worker)]
+[Pref="dom_testbinding_enabled", Exposed=(Window,Worker)]
 interface TestBindingPairIterable {
   [Throws] constructor();
   undefined add(DOMString key, unsigned long value);
diff --git a/components/script/dom/webidls/TestBindingProxy.webidl b/components/script/dom/webidls/TestBindingProxy.webidl
index b16d5104242..957db0f0302 100644
--- a/components/script/dom/webidls/TestBindingProxy.webidl
+++ b/components/script/dom/webidls/TestBindingProxy.webidl
@@ -11,7 +11,7 @@
 // This interface is entirely internal to Servo, and should not be accessible to
 // web pages.
 
-[Pref="dom.testbinding.enabled", Exposed=(Window,Worker)]
+[Pref="dom_testbinding_enabled", Exposed=(Window,Worker)]
 interface TestBindingProxy : TestBinding {
   readonly attribute unsigned long length;
 
diff --git a/components/script/dom/webidls/TestBindingSetlike.webidl b/components/script/dom/webidls/TestBindingSetlike.webidl
index c8cfcf73b86..16b264bb9f6 100644
--- a/components/script/dom/webidls/TestBindingSetlike.webidl
+++ b/components/script/dom/webidls/TestBindingSetlike.webidl
@@ -5,7 +5,7 @@
 // This interface is entirely internal to Servo, and should not be accessible to
 // web pages.
 
-[Pref="dom.testbinding.enabled", Exposed=(Window,Worker)]
+[Pref="dom_testbinding_enabled", Exposed=(Window,Worker)]
 interface TestBindingSetlike {
   [Throws]
   constructor();
diff --git a/components/script/dom/webidls/TestRunner.webidl b/components/script/dom/webidls/TestRunner.webidl
index 448be17c4d4..4be17153247 100644
--- a/components/script/dom/webidls/TestRunner.webidl
+++ b/components/script/dom/webidls/TestRunner.webidl
@@ -6,7 +6,7 @@
 
 // callback BluetoothManualChooserEventsCallback = void(sequence<DOMString> events);
 
-[Pref="dom.bluetooth.testing.enabled", Exposed=Window]
+[Pref="dom_bluetooth_testing_enabled", Exposed=Window]
 interface TestRunner {
   [Throws]
   undefined setBluetoothMockDataSet(DOMString dataSetName);
diff --git a/components/script/dom/webidls/TestWorklet.webidl b/components/script/dom/webidls/TestWorklet.webidl
index 81b02da0731..8e5898736b0 100644
--- a/components/script/dom/webidls/TestWorklet.webidl
+++ b/components/script/dom/webidls/TestWorklet.webidl
@@ -5,7 +5,7 @@
 // This interface is entirely internal to Servo, and should not be accessible to
 // web pages.
 
-[Pref="dom.worklet.testing.enabled", Exposed=(Window)]
+[Pref="dom_worklet_testing_enabled", Exposed=(Window)]
 interface TestWorklet {
    [Throws] constructor();
    [NewObject] Promise<undefined> addModule(USVString moduleURL, optional WorkletOptions options = {});
diff --git a/components/script/dom/webidls/TestWorkletGlobalScope.webidl b/components/script/dom/webidls/TestWorkletGlobalScope.webidl
index 1c2735dbc65..86599a2c257 100644
--- a/components/script/dom/webidls/TestWorkletGlobalScope.webidl
+++ b/components/script/dom/webidls/TestWorkletGlobalScope.webidl
@@ -5,7 +5,7 @@
 // This interface is entirely internal to Servo, and should not be accessible to
 // web pages.
 
-[Global=(Worklet,TestWorklet), Pref="dom.worklet.enabled", Exposed=TestWorklet]
+[Global=(Worklet,TestWorklet), Pref="dom_worklet_enabled", Exposed=TestWorklet]
 interface TestWorkletGlobalScope : WorkletGlobalScope {
     undefined registerKeyValue(DOMString key, DOMString value);
 };
diff --git a/components/script/dom/webidls/TextMetrics.webidl b/components/script/dom/webidls/TextMetrics.webidl
index efba27450fe..ebf0bd8a3dc 100644
--- a/components/script/dom/webidls/TextMetrics.webidl
+++ b/components/script/dom/webidls/TextMetrics.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://html.spec.whatwg.org/multipage/#textmetrics
-[Exposed=(PaintWorklet, Window, Worker), Pref="dom.canvas_text.enabled"]
+[Exposed=(PaintWorklet, Window, Worker), Pref="dom_canvas_text_enabled"]
 interface TextMetrics {
   // x-direction
   readonly attribute double width; // advance width
diff --git a/components/script/dom/webidls/VTTCue.webidl b/components/script/dom/webidls/VTTCue.webidl
index 073aa12f79b..ccbd342a788 100644
--- a/components/script/dom/webidls/VTTCue.webidl
+++ b/components/script/dom/webidls/VTTCue.webidl
@@ -11,7 +11,7 @@ enum LineAlignSetting { "start", "center", "end" };
 enum PositionAlignSetting { "line-left", "center", "line-right", "auto" };
 enum AlignSetting { "start", "center", "end", "left", "right" };
 
-[Pref="dom.webvtt.enabled", Exposed=Window]
+[Pref="dom_webvtt_enabled", Exposed=Window]
 interface VTTCue : TextTrackCue {
   constructor(double startTime, double endTime, DOMString text);
   attribute VTTRegion? region;
diff --git a/components/script/dom/webidls/VTTRegion.webidl b/components/script/dom/webidls/VTTRegion.webidl
index 12fbe16170b..f4a616ef323 100644
--- a/components/script/dom/webidls/VTTRegion.webidl
+++ b/components/script/dom/webidls/VTTRegion.webidl
@@ -6,7 +6,7 @@
 
 enum ScrollSetting { "" /* none */, "up"};
 
-[Pref="dom.webvtt.enabled", Exposed=Window]
+[Pref="dom_webvtt_enabled", Exposed=Window]
 interface VTTRegion {
   [Throws] constructor();
   attribute DOMString id;
diff --git a/components/script/dom/webidls/WebGLQuery.webidl b/components/script/dom/webidls/WebGLQuery.webidl
index 04b3711dd86..feea145c611 100644
--- a/components/script/dom/webidls/WebGLQuery.webidl
+++ b/components/script/dom/webidls/WebGLQuery.webidl
@@ -6,6 +6,6 @@
 // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.8
 //
 
-[Exposed=Window, Pref="dom.webgl2.enabled"]
+[Exposed=Window, Pref="dom_webgl2_enabled"]
 interface WebGLQuery : WebGLObject {
 };
diff --git a/components/script/dom/webidls/WebGLSampler.webidl b/components/script/dom/webidls/WebGLSampler.webidl
index 90c66b65a1d..4669aebeabd 100644
--- a/components/script/dom/webidls/WebGLSampler.webidl
+++ b/components/script/dom/webidls/WebGLSampler.webidl
@@ -6,6 +6,6 @@
 // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.8
 //
 
-[Exposed=Window, Pref="dom.webgl2.enabled"]
+[Exposed=Window, Pref="dom_webgl2_enabled"]
 interface WebGLSampler : WebGLObject {
 };
diff --git a/components/script/dom/webidls/WebGLSync.webidl b/components/script/dom/webidls/WebGLSync.webidl
index f8cd33ef9ce..66640a888f0 100644
--- a/components/script/dom/webidls/WebGLSync.webidl
+++ b/components/script/dom/webidls/WebGLSync.webidl
@@ -6,6 +6,6 @@
 // https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.14
 //
 
-[Exposed=Window, Pref="dom.webgl2.enabled"]
+[Exposed=Window, Pref="dom_webgl2_enabled"]
 interface WebGLSync : WebGLObject {
 };
diff --git a/components/script/dom/webidls/WebGLTransformFeedback.webidl b/components/script/dom/webidls/WebGLTransformFeedback.webidl
index 871c0f15c7b..ee666366dd4 100644
--- a/components/script/dom/webidls/WebGLTransformFeedback.webidl
+++ b/components/script/dom/webidls/WebGLTransformFeedback.webidl
@@ -6,6 +6,6 @@
 // https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.15
 //
 
-[Exposed=(Window), Pref="dom.webgl2.enabled"]
+[Exposed=(Window), Pref="dom_webgl2_enabled"]
 interface WebGLTransformFeedback : WebGLObject {
 };
diff --git a/components/script/dom/webidls/WebGLVertexArrayObject.webidl b/components/script/dom/webidls/WebGLVertexArrayObject.webidl
index a42d8cbe051..c6649e17ef8 100644
--- a/components/script/dom/webidls/WebGLVertexArrayObject.webidl
+++ b/components/script/dom/webidls/WebGLVertexArrayObject.webidl
@@ -6,6 +6,6 @@
 // https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.17
 //
 
-[Exposed=(Window), Pref="dom.webgl2.enabled"]
+[Exposed=(Window), Pref="dom_webgl2_enabled"]
 interface WebGLVertexArrayObject : WebGLObject {
 };
diff --git a/components/script/dom/webidls/WebGPU.webidl b/components/script/dom/webidls/WebGPU.webidl
index 5f0572c768a..41bee4718cb 100644
--- a/components/script/dom/webidls/WebGPU.webidl
+++ b/components/script/dom/webidls/WebGPU.webidl
@@ -16,7 +16,7 @@ dictionary GPUObjectDescriptorBase {
     USVString label = "";
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUSupportedLimits {
     readonly attribute unsigned long maxTextureDimension1D;
     readonly attribute unsigned long maxTextureDimension2D;
@@ -52,17 +52,17 @@ interface GPUSupportedLimits {
     readonly attribute unsigned long maxComputeWorkgroupsPerDimension;
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUSupportedFeatures {
     readonly setlike<DOMString>;
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface WGSLLanguageFeatures {
     readonly setlike<DOMString>;
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUAdapterInfo {
     readonly attribute DOMString vendor;
     readonly attribute DOMString architecture;
@@ -71,13 +71,13 @@ interface GPUAdapterInfo {
 };
 
 interface mixin NavigatorGPU {
-    [SameObject, Pref="dom.webgpu.enabled", Exposed=(Window /* ,DedicatedWorker */)] readonly attribute GPU gpu;
+    [SameObject, Pref="dom_webgpu_enabled", Exposed=(Window /* ,DedicatedWorker */)] readonly attribute GPU gpu;
 };
 
 Navigator includes NavigatorGPU;
 WorkerNavigator includes NavigatorGPU;
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPU {
     [NewObject]
     Promise<GPUAdapter?> requestAdapter(optional GPURequestAdapterOptions options = {});
@@ -95,7 +95,7 @@ enum GPUPowerPreference {
     "high-performance"
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUAdapter {
     [SameObject] readonly attribute GPUSupportedFeatures features;
     [SameObject] readonly attribute GPUSupportedLimits limits;
@@ -129,7 +129,7 @@ enum GPUFeatureName {
     "dual-source-blending",
 };
 
-[Exposed=(Window, DedicatedWorker), /*Serializable,*/ Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), /*Serializable,*/ Pref="dom_webgpu_enabled"]
 interface GPUDevice: EventTarget {
     [SameObject] readonly attribute GPUSupportedFeatures features;
     [SameObject] readonly attribute GPUSupportedLimits limits;
@@ -170,7 +170,7 @@ interface GPUDevice: EventTarget {
 };
 GPUDevice includes GPUObjectBase;
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUBuffer {
     readonly attribute GPUSize64Out size;
     readonly attribute GPUFlagsConstant usage;
@@ -201,7 +201,7 @@ dictionary GPUBufferDescriptor : GPUObjectDescriptorBase {
 };
 
 typedef [EnforceRange] unsigned long GPUBufferUsageFlags;
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 namespace GPUBufferUsage {
     const GPUFlagsConstant MAP_READ      = 0x0001;
     const GPUFlagsConstant MAP_WRITE     = 0x0002;
@@ -216,13 +216,13 @@ namespace GPUBufferUsage {
 };
 
 typedef [EnforceRange] unsigned long GPUMapModeFlags;
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 namespace GPUMapMode {
     const GPUFlagsConstant READ  = 0x0001;
     const GPUFlagsConstant WRITE = 0x0002;
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable , Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable , Pref="dom_webgpu_enabled"]
 interface GPUTexture {
     [Throws, NewObject]
     GPUTextureView createView(optional GPUTextureViewDescriptor descriptor = {});
@@ -257,7 +257,7 @@ enum GPUTextureDimension {
 };
 
 typedef [EnforceRange] unsigned long GPUTextureUsageFlags;
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUTextureUsage {
     const GPUTextureUsageFlags COPY_SRC          = 0x01;
     const GPUTextureUsageFlags COPY_DST          = 0x02;
@@ -266,7 +266,7 @@ interface GPUTextureUsage {
     const GPUTextureUsageFlags RENDER_ATTACHMENT = 0x10;
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUTextureView {
 };
 GPUTextureView includes GPUObjectBase;
@@ -418,7 +418,7 @@ enum GPUTextureFormat {
     "astc-12x12-unorm-srgb",
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUSampler {
 };
 GPUSampler includes GPUObjectBase;
@@ -458,7 +458,7 @@ enum GPUCompareFunction {
     "always"
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUBindGroupLayout {
 };
 GPUBindGroupLayout includes GPUObjectBase;
@@ -479,7 +479,7 @@ dictionary GPUBindGroupLayoutEntry {
 };
 
 typedef [EnforceRange] unsigned long GPUShaderStageFlags;
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUShaderStage {
     const GPUShaderStageFlags VERTEX = 1;
     const GPUShaderStageFlags FRAGMENT = 2;
@@ -537,7 +537,7 @@ dictionary GPUStorageTextureBindingLayout {
 dictionary GPUExternalTextureBindingLayout {
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUBindGroup {
 };
 GPUBindGroup includes GPUObjectBase;
@@ -560,7 +560,7 @@ dictionary GPUBufferBinding {
     GPUSize64 size;
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUPipelineLayout {
 };
 GPUPipelineLayout includes GPUObjectBase;
@@ -569,7 +569,7 @@ dictionary GPUPipelineLayoutDescriptor : GPUObjectDescriptorBase {
     required sequence<GPUBindGroupLayout> bindGroupLayouts;
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUShaderModule {
     Promise<GPUCompilationInfo> getCompilationInfo();
 };
@@ -587,7 +587,7 @@ enum GPUCompilationMessageType {
     "info"
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUCompilationMessage {
     readonly attribute DOMString message;
     readonly attribute GPUCompilationMessageType type;
@@ -597,13 +597,13 @@ interface GPUCompilationMessage {
     readonly attribute unsigned long long length;
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUCompilationInfo {
     //readonly attribute FrozenArray<GPUCompilationMessage> messages;
     readonly attribute any messages;
 };
 
-[Exposed=(Window, Worker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, Worker), Pref="dom_webgpu_enabled"]
 interface GPUPipelineError : DOMException {
     constructor(optional DOMString message = "", GPUPipelineErrorInit options);
     readonly attribute GPUPipelineErrorReason reason;
@@ -638,7 +638,7 @@ dictionary GPUProgrammableStage {
 
 typedef double GPUPipelineConstantValue; // May represent WGSL's bool, f32, i32, u32, and f16 if enabled.
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUComputePipeline {
 };
 GPUComputePipeline includes GPUObjectBase;
@@ -648,7 +648,7 @@ dictionary GPUComputePipelineDescriptor : GPUPipelineDescriptorBase {
     required GPUProgrammableStage compute;
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPURenderPipeline {
 };
 GPURenderPipeline includes GPUObjectBase;
@@ -712,7 +712,7 @@ dictionary GPUBlendState {
 };
 
 typedef [EnforceRange] unsigned long GPUColorWriteFlags;
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPUColorWrite {
     const GPUColorWriteFlags RED   = 0x1;
     const GPUColorWriteFlags GREEN = 0x2;
@@ -873,7 +873,7 @@ dictionary GPUImageCopyExternalImage {
     boolean flipY = false;
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUCommandBuffer {
 };
 GPUCommandBuffer includes GPUObjectBase;
@@ -881,7 +881,7 @@ GPUCommandBuffer includes GPUObjectBase;
 dictionary GPUCommandBufferDescriptor : GPUObjectDescriptorBase {
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUCommandEncoder {
     [NewObject]
     GPUComputePassEncoder beginComputePass(optional GPUComputePassDescriptor descriptor = {});
@@ -939,11 +939,11 @@ dictionary GPUCommandEncoderDescriptor : GPUObjectDescriptorBase {
     boolean measureExecutionTime = false;
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUComputePassEncoder {
     undefined setPipeline(GPUComputePipeline pipeline);
     undefined dispatchWorkgroups(GPUSize32 x, optional GPUSize32 y = 1, optional GPUSize32 z = 1);
-    //[Pref="dom.webgpu.indirect-dispatch.enabled"]
+    //[Pref="dom_webgpu_indirect-dispatch.enabled"]
     undefined dispatchWorkgroupsIndirect(GPUBuffer indirectBuffer, GPUSize64 indirectOffset);
 
     undefined end();
@@ -954,7 +954,7 @@ GPUComputePassEncoder includes GPUProgrammablePassEncoder;
 dictionary GPUComputePassDescriptor : GPUObjectDescriptorBase {
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPURenderPassEncoder {
     undefined setViewport(float x, float y,
                           float width, float height,
@@ -1063,13 +1063,13 @@ interface mixin GPURenderEncoderBase {
                           optional GPUSignedOffset32 baseVertex = 0,
                           optional GPUSize32 firstInstance = 0);
 
-    //[Pref="dom.webgpu.indirect-dispatch.enabled"]
+    //[Pref="dom_webgpu_indirect-dispatch.enabled"]
     undefined drawIndirect(GPUBuffer indirectBuffer, GPUSize64 indirectOffset);
-    //[Pref="dom.webgpu.indirect-dispatch.enabled"]
+    //[Pref="dom_webgpu_indirect-dispatch.enabled"]
     undefined drawIndexedIndirect(GPUBuffer indirectBuffer, GPUSize64 indirectOffset);
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPURenderBundle {
 };
 GPURenderBundle includes GPUObjectBase;
@@ -1077,7 +1077,7 @@ GPURenderBundle includes GPUObjectBase;
 dictionary GPURenderBundleDescriptor : GPUObjectDescriptorBase {
 };
 
-[Exposed=(Window, DedicatedWorker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Pref="dom_webgpu_enabled"]
 interface GPURenderBundleEncoder {
     GPURenderBundle finish(optional GPURenderBundleDescriptor descriptor = {});
 };
@@ -1090,7 +1090,7 @@ dictionary GPURenderBundleEncoderDescriptor : GPURenderPassLayout {
     boolean stencilReadOnly = false;
 };
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUQueue {
     undefined submit(sequence<GPUCommandBuffer> buffers);
 
@@ -1119,7 +1119,7 @@ interface GPUQueue {
 };
 GPUQueue includes GPUObjectBase;
 
-[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom_webgpu_enabled"]
 interface GPUQuerySet {
     undefined destroy();
 };
@@ -1173,7 +1173,7 @@ enum GPUDeviceLostReason {
     "destroyed",
 };
 
-[Exposed=(Window, Worker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, Worker), Pref="dom_webgpu_enabled"]
 interface GPUDeviceLostInfo {
     readonly attribute GPUDeviceLostReason reason;
     readonly attribute DOMString message;
@@ -1183,24 +1183,24 @@ partial interface GPUDevice {
     readonly attribute Promise<GPUDeviceLostInfo> lost;
 };
 
-[Exposed=(Window, Worker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, Worker), Pref="dom_webgpu_enabled"]
 interface GPUError {
     readonly attribute DOMString message;
 };
 
-[Exposed=(Window, Worker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, Worker), Pref="dom_webgpu_enabled"]
 interface GPUValidationError
         : GPUError {
     constructor(DOMString message);
 };
 
-[Exposed=(Window, Worker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, Worker), Pref="dom_webgpu_enabled"]
 interface GPUOutOfMemoryError
         : GPUError {
     constructor(DOMString message);
 };
 
-[Exposed=(Window, Worker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, Worker), Pref="dom_webgpu_enabled"]
 interface GPUInternalError
         : GPUError {
     constructor(DOMString message);
@@ -1218,7 +1218,7 @@ partial interface GPUDevice {
     Promise<GPUError?> popErrorScope();
 };
 
-[Exposed=(Window, Worker), Pref="dom.webgpu.enabled"]
+[Exposed=(Window, Worker), Pref="dom_webgpu_enabled"]
 interface GPUUncapturedErrorEvent : Event {
     constructor(
         DOMString type,
diff --git a/components/script/dom/webidls/Window.webidl b/components/script/dom/webidls/Window.webidl
index 84871494d2b..64d7563b38e 100644
--- a/components/script/dom/webidls/Window.webidl
+++ b/components/script/dom/webidls/Window.webidl
@@ -15,7 +15,7 @@
   [PutForwards=href, LegacyUnforgeable, CrossOriginReadable, CrossOriginWritable]
     readonly attribute Location location;
   readonly attribute History history;
-  [Pref="dom.customelements.enabled"]
+  [Pref="dom_customelements_enabled"]
   readonly attribute CustomElementRegistry customElements;
   //[Replaceable] readonly attribute BarProp locationbar;
   //[Replaceable] readonly attribute BarProp menubar;
@@ -136,11 +136,11 @@ partial interface Window {
 
 // Proprietary extensions.
 partial interface Window {
-  [Pref="dom.servo_helpers.enabled"]
+  [Pref="dom_servo_helpers_enabled"]
   undefined debug(DOMString arg);
-  [Pref="dom.servo_helpers.enabled"]
+  [Pref="dom_servo_helpers_enabled"]
   undefined gc();
-  [Pref="dom.servo_helpers.enabled"]
+  [Pref="dom_servo_helpers_enabled"]
   undefined js_backtrace();
 };
 
@@ -168,13 +168,13 @@ callback FrameRequestCallback = undefined (DOMHighResTimeStamp time);
 
 // https://webbluetoothcg.github.io/web-bluetooth/tests#test-interfaces
 partial interface Window {
-   [Pref="dom.bluetooth.testing.enabled", Exposed=Window]
+   [Pref="dom_bluetooth_testing_enabled", Exposed=Window]
    readonly attribute TestRunner testRunner;
    //readonly attribute EventSender eventSender;
 };
 
 partial interface Window {
-   [Pref="css.animations.testing.enabled"]
+   [Pref="css_animations_testing_enabled"]
    readonly attribute unsigned long runningAnimationCount;
 };
 
diff --git a/components/script/dom/webidls/WindowOrWorkerGlobalScope.webidl b/components/script/dom/webidls/WindowOrWorkerGlobalScope.webidl
index dbcce406a43..d9204c11774 100644
--- a/components/script/dom/webidls/WindowOrWorkerGlobalScope.webidl
+++ b/components/script/dom/webidls/WindowOrWorkerGlobalScope.webidl
@@ -24,7 +24,7 @@ interface mixin WindowOrWorkerGlobalScope {
   undefined queueMicrotask(VoidFunction callback);
 
   // ImageBitmap
-  [Pref="dom.imagebitmap.enabled"]
+  [Pref="dom_imagebitmap_enabled"]
   Promise<ImageBitmap> createImageBitmap(ImageBitmapSource image, optional ImageBitmapOptions options = {});
   // Promise<ImageBitmap> createImageBitmap(
   //   ImageBitmapSource image, long sx, long sy, long sw, long sh, optional ImageBitmapOptions options);
diff --git a/components/script/dom/webidls/WorkerNavigator.webidl b/components/script/dom/webidls/WorkerNavigator.webidl
index 3de4be96ebc..33ddfade93d 100644
--- a/components/script/dom/webidls/WorkerNavigator.webidl
+++ b/components/script/dom/webidls/WorkerNavigator.webidl
@@ -14,6 +14,6 @@ WorkerNavigator includes NavigatorConcurrentHardware;
 
 [Exposed=(Worker)]
 partial interface WorkerNavigator {
-  [Pref="dom.permissions.enabled"] readonly attribute Permissions permissions;
+  [Pref="dom_permissions_enabled"] readonly attribute Permissions permissions;
 };
 
diff --git a/components/script/dom/webidls/Worklet.webidl b/components/script/dom/webidls/Worklet.webidl
index 249f9c9d470..a656c1e3865 100644
--- a/components/script/dom/webidls/Worklet.webidl
+++ b/components/script/dom/webidls/Worklet.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://drafts.css-houdini.org/worklets/#worklet
-[Pref="dom.worklet.enabled", Exposed=(Window)]
+[Pref="dom_worklet_enabled", Exposed=(Window)]
 interface Worklet {
     [NewObject] Promise<undefined> addModule(USVString moduleURL, optional WorkletOptions options = {});
 };
diff --git a/components/script/dom/webidls/WorkletGlobalScope.webidl b/components/script/dom/webidls/WorkletGlobalScope.webidl
index 21f7a7e0af0..33283c84161 100644
--- a/components/script/dom/webidls/WorkletGlobalScope.webidl
+++ b/components/script/dom/webidls/WorkletGlobalScope.webidl
@@ -5,6 +5,6 @@
 // https://drafts.css-houdini.org/worklets/#workletglobalscope
 // TODO: The spec IDL doesn't make this a subclass of EventTarget
 //       https://github.com/whatwg/html/issues/2611
-[Pref="dom.worklet.enabled", Exposed=Worklet]
+[Pref="dom_worklet_enabled", Exposed=Worklet]
 interface WorkletGlobalScope: GlobalScope {
 };
diff --git a/components/script/dom/webidls/XPathEvaluator.webidl b/components/script/dom/webidls/XPathEvaluator.webidl
index 8586b19232b..ebb505c104c 100644
--- a/components/script/dom/webidls/XPathEvaluator.webidl
+++ b/components/script/dom/webidls/XPathEvaluator.webidl
@@ -4,13 +4,13 @@
 
 // https://dom.spec.whatwg.org/#mixin-xpathevaluatorbase
 interface mixin XPathEvaluatorBase {
-  [NewObject, Throws, Pref="dom.xpath.enabled"] XPathExpression createExpression(
+  [NewObject, Throws, Pref="dom_xpath_enabled"] XPathExpression createExpression(
     DOMString expression,
     optional XPathNSResolver? resolver = null
   );
   Node createNSResolver(Node nodeResolver); // legacy
   // XPathResult.ANY_TYPE = 0
-  [Throws, Pref="dom.xpath.enabled"] XPathResult evaluate(
+  [Throws, Pref="dom_xpath_enabled"] XPathResult evaluate(
     DOMString expression,
     Node contextNode,
     optional XPathNSResolver? resolver = null,
@@ -22,7 +22,7 @@ interface mixin XPathEvaluatorBase {
 Document includes XPathEvaluatorBase;
 
 // https://dom.spec.whatwg.org/#interface-xpathevaluator
-[Exposed=Window, Pref="dom.xpath.enabled"]
+[Exposed=Window, Pref="dom_xpath_enabled"]
 interface XPathEvaluator {
   constructor();
 };
diff --git a/components/script/dom/webidls/XPathExpression.webidl b/components/script/dom/webidls/XPathExpression.webidl
index bf5ba2b83aa..29cbd23e757 100644
--- a/components/script/dom/webidls/XPathExpression.webidl
+++ b/components/script/dom/webidls/XPathExpression.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://dom.spec.whatwg.org/#interface-xpathexpression
-[Exposed=Window, Pref="dom.xpath.enabled"]
+[Exposed=Window, Pref="dom_xpath_enabled"]
 interface XPathExpression {
   // XPathResult.ANY_TYPE = 0
   [Throws] XPathResult evaluate(
diff --git a/components/script/dom/webidls/XPathResult.webidl b/components/script/dom/webidls/XPathResult.webidl
index 25e87e3024a..ed0e9804ca4 100644
--- a/components/script/dom/webidls/XPathResult.webidl
+++ b/components/script/dom/webidls/XPathResult.webidl
@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 // https://dom.spec.whatwg.org/#interface-xpathresult
-[Exposed=Window, Pref="dom.xpath.enabled"]
+[Exposed=Window, Pref="dom_xpath_enabled"]
 interface XPathResult {
   const unsigned short ANY_TYPE = 0;
   const unsigned short NUMBER_TYPE = 1;
diff --git a/components/script/dom/webidls/XRBoundedReferenceSpace.webidl b/components/script/dom/webidls/XRBoundedReferenceSpace.webidl
index c028f740c87..9bf63f7f685 100644
--- a/components/script/dom/webidls/XRBoundedReferenceSpace.webidl
+++ b/components/script/dom/webidls/XRBoundedReferenceSpace.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrboundedreferencespace-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRBoundedReferenceSpace : XRReferenceSpace {
   readonly attribute /*FrozenArray<DOMPointReadOnly>*/ any boundsGeometry;
 };
diff --git a/components/script/dom/webidls/XRCompositionLayer.webidl b/components/script/dom/webidls/XRCompositionLayer.webidl
index e8cedf71240..bdfe3435965 100644
--- a/components/script/dom/webidls/XRCompositionLayer.webidl
+++ b/components/script/dom/webidls/XRCompositionLayer.webidl
@@ -8,7 +8,7 @@
 // https://github.com/servo/servo/issues/27493
 
 // https://immersive-web.github.io/layers/#xrcompositionlayer
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRCompositionLayer : XRLayer {
 //   readonly attribute XRLayerLayout layout;
 //
diff --git a/components/script/dom/webidls/XRCubeLayer.webidl b/components/script/dom/webidls/XRCubeLayer.webidl
index 1b213f34be3..30744201a87 100644
--- a/components/script/dom/webidls/XRCubeLayer.webidl
+++ b/components/script/dom/webidls/XRCubeLayer.webidl
@@ -9,7 +9,7 @@
 
 // https://immersive-web.github.io/layers/#xrcubelayer
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRCubeLayer : XRCompositionLayer {
 //   attribute XRSpace space;
 //   attribute DOMPointReadOnly orientation;
diff --git a/components/script/dom/webidls/XRCylinderLayer.webidl b/components/script/dom/webidls/XRCylinderLayer.webidl
index e290aecdee4..c20801f81a0 100644
--- a/components/script/dom/webidls/XRCylinderLayer.webidl
+++ b/components/script/dom/webidls/XRCylinderLayer.webidl
@@ -8,7 +8,7 @@
 // https://github.com/servo/servo/issues/27493
 
 // https://immersive-web.github.io/layers/#xrcylinderlayer
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRCylinderLayer : XRCompositionLayer {
 //   attribute XRSpace space;
 //   attribute XRRigidTransform transform;
diff --git a/components/script/dom/webidls/XREquirectLayer.webidl b/components/script/dom/webidls/XREquirectLayer.webidl
index f7eeb327b9a..7b1d1584d62 100644
--- a/components/script/dom/webidls/XREquirectLayer.webidl
+++ b/components/script/dom/webidls/XREquirectLayer.webidl
@@ -8,7 +8,7 @@
 // https://github.com/servo/servo/issues/27493
 
 // https://immersive-web.github.io/layers/#xrequirectlayer
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XREquirectLayer : XRCompositionLayer {
 //   attribute XRSpace space;
 //   attribute XRRigidTransform transform;
diff --git a/components/script/dom/webidls/XRFrame.webidl b/components/script/dom/webidls/XRFrame.webidl
index 2e05028ec0c..d5ec4b6ef21 100644
--- a/components/script/dom/webidls/XRFrame.webidl
+++ b/components/script/dom/webidls/XRFrame.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrframe-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRFrame {
   [SameObject] readonly attribute XRSession session;
   readonly attribute DOMHighResTimeStamp predictedDisplayTime;
@@ -15,12 +15,12 @@ interface XRFrame {
   [Throws] XRPose? getPose(XRSpace space, XRSpace baseSpace);
 
   // WebXR Hand Input
-  [Pref="dom.webxr.hands.enabled", Throws]
+  [Pref="dom_webxr_hands_enabled", Throws]
   XRJointPose? getJointPose(XRJointSpace joint, XRSpace baseSpace);
-  [Pref="dom.webxr.hands.enabled", Throws]
+  [Pref="dom_webxr_hands_enabled", Throws]
   boolean fillJointRadii(sequence<XRJointSpace> jointSpaces, Float32Array radii);
 
-  [Pref="dom.webxr.hands.enabled", Throws]
+  [Pref="dom_webxr_hands_enabled", Throws]
   boolean fillPoses(sequence<XRSpace> spaces, XRSpace baseSpace, Float32Array transforms);
 
   // WebXR Hit Test
diff --git a/components/script/dom/webidls/XRHand.webidl b/components/script/dom/webidls/XRHand.webidl
index ad46e719f2b..6749eab8dd5 100644
--- a/components/script/dom/webidls/XRHand.webidl
+++ b/components/script/dom/webidls/XRHand.webidl
@@ -39,7 +39,7 @@ enum XRHandJoint {
     "pinky-finger-tip"
 };
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.hands.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_hands_enabled"]
 interface XRHand {
     iterable<XRHandJoint, XRJointSpace>;
 
diff --git a/components/script/dom/webidls/XRInputSource.webidl b/components/script/dom/webidls/XRInputSource.webidl
index 820f24c363f..7b82b050777 100644
--- a/components/script/dom/webidls/XRInputSource.webidl
+++ b/components/script/dom/webidls/XRInputSource.webidl
@@ -19,7 +19,7 @@ enum XRTargetRayMode {
   "transient-pointer"
 };
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRInputSource {
   readonly attribute XRHandedness handedness;
   readonly attribute XRTargetRayMode targetRayMode;
@@ -32,6 +32,6 @@ interface XRInputSource {
   [SameObject] readonly attribute Gamepad? gamepad;
 
   // Hand Input
-  [Pref="dom.webxr.hands.enabled"]
+  [Pref="dom_webxr_hands_enabled"]
   readonly attribute XRHand? hand;
 };
diff --git a/components/script/dom/webidls/XRInputSourceArray.webidl b/components/script/dom/webidls/XRInputSourceArray.webidl
index 5987c0039d3..093eab67ed9 100644
--- a/components/script/dom/webidls/XRInputSourceArray.webidl
+++ b/components/script/dom/webidls/XRInputSourceArray.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrinputsourcearray-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRInputSourceArray {
   iterable<XRInputSource>;
   readonly attribute unsigned long length;
diff --git a/components/script/dom/webidls/XRInputSourceEvent.webidl b/components/script/dom/webidls/XRInputSourceEvent.webidl
index e2cb1b394c9..11055b3f247 100644
--- a/components/script/dom/webidls/XRInputSourceEvent.webidl
+++ b/components/script/dom/webidls/XRInputSourceEvent.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrinputsourceevent-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRInputSourceEvent : Event {
   [Throws] constructor(DOMString type, XRInputSourceEventInit eventInitDict);
   [SameObject] readonly attribute XRFrame frame;
diff --git a/components/script/dom/webidls/XRInputSourcesChangeEvent.webidl b/components/script/dom/webidls/XRInputSourcesChangeEvent.webidl
index 25a4885cca3..f6b65d12a09 100644
--- a/components/script/dom/webidls/XRInputSourcesChangeEvent.webidl
+++ b/components/script/dom/webidls/XRInputSourcesChangeEvent.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrinputsourceschangedevent-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.test"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_test"]
 interface XRInputSourcesChangeEvent : Event {
   constructor(DOMString type, XRInputSourcesChangeEventInit eventInitDict);
   [SameObject] readonly attribute XRSession session;
diff --git a/components/script/dom/webidls/XRJointPose.webidl b/components/script/dom/webidls/XRJointPose.webidl
index e824745588e..73bde0ca6e6 100644
--- a/components/script/dom/webidls/XRJointPose.webidl
+++ b/components/script/dom/webidls/XRJointPose.webidl
@@ -6,7 +6,7 @@
 
 // https://github.com/immersive-web/webxr-hands-input/blob/master/explainer.md
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.hands.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_hands_enabled"]
 interface XRJointPose: XRPose {
     readonly attribute float? radius;
 };
diff --git a/components/script/dom/webidls/XRJointSpace.webidl b/components/script/dom/webidls/XRJointSpace.webidl
index 7326e9990a1..2eeca7edc15 100644
--- a/components/script/dom/webidls/XRJointSpace.webidl
+++ b/components/script/dom/webidls/XRJointSpace.webidl
@@ -6,7 +6,7 @@
 
 // https://github.com/immersive-web/webxr-hands-input/blob/master/explainer.md
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.hands.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_hands_enabled"]
 interface XRJointSpace: XRSpace {
   readonly attribute XRHandJoint jointName;
 };
diff --git a/components/script/dom/webidls/XRLayer.webidl b/components/script/dom/webidls/XRLayer.webidl
index 122946defb9..fdc9b2bee3a 100644
--- a/components/script/dom/webidls/XRLayer.webidl
+++ b/components/script/dom/webidls/XRLayer.webidl
@@ -5,5 +5,5 @@
 // skip-unless CARGO_FEATURE_WEBXR
 
 // https://immersive-web.github.io/webxr/#xrlayer
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRLayer : EventTarget {};
diff --git a/components/script/dom/webidls/XRLayerEvent.webidl b/components/script/dom/webidls/XRLayerEvent.webidl
index e45f116da34..553a70fcaec 100644
--- a/components/script/dom/webidls/XRLayerEvent.webidl
+++ b/components/script/dom/webidls/XRLayerEvent.webidl
@@ -5,7 +5,7 @@
 // skip-unless CARGO_FEATURE_WEBXR
 
 // https://immersive-web.github.io/layers/#xrlayerevent-interface
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRLayerEvent : Event {
   constructor(DOMString type, XRLayerEventInit eventInitDict);
   [SameObject] readonly attribute XRLayer layer;
diff --git a/components/script/dom/webidls/XRMediaBinding.webidl b/components/script/dom/webidls/XRMediaBinding.webidl
index 4c3bfc91e80..558aa0596c3 100644
--- a/components/script/dom/webidls/XRMediaBinding.webidl
+++ b/components/script/dom/webidls/XRMediaBinding.webidl
@@ -5,7 +5,7 @@
 // skip-unless CARGO_FEATURE_WEBXR
 
 // https://immersive-web.github.io/layers/#xrmediabindingtype
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRMediaBinding {
   [Throws] constructor(XRSession session);
 
diff --git a/components/script/dom/webidls/XRPose.webidl b/components/script/dom/webidls/XRPose.webidl
index dab2d9e7af9..2ac5f372cdd 100644
--- a/components/script/dom/webidls/XRPose.webidl
+++ b/components/script/dom/webidls/XRPose.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrpose-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRPose {
   [SameObject] readonly attribute XRRigidTransform transform;
   [SameObject] readonly attribute DOMPointReadOnly? linearVelocity;
diff --git a/components/script/dom/webidls/XRProjectionLayer.webidl b/components/script/dom/webidls/XRProjectionLayer.webidl
index 0c812948795..bdb9de13dd2 100644
--- a/components/script/dom/webidls/XRProjectionLayer.webidl
+++ b/components/script/dom/webidls/XRProjectionLayer.webidl
@@ -8,7 +8,7 @@
 // https://github.com/servo/servo/issues/27493
 
 // https://immersive-web.github.io/layers/#xrprojectionlayer
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRProjectionLayer : XRCompositionLayer {
 //   readonly attribute boolean ignoreDepthValues;
 };
diff --git a/components/script/dom/webidls/XRQuadLayer.webidl b/components/script/dom/webidls/XRQuadLayer.webidl
index a4c43b0b62e..0b4afcac9be 100644
--- a/components/script/dom/webidls/XRQuadLayer.webidl
+++ b/components/script/dom/webidls/XRQuadLayer.webidl
@@ -8,7 +8,7 @@
 // https://github.com/servo/servo/issues/27493
 
 // https://immersive-web.github.io/layers/#xrquadlayer
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRQuadLayer : XRCompositionLayer {
 //   attribute XRSpace space;
 //   attribute XRRigidTransform transform;
diff --git a/components/script/dom/webidls/XRRay.webidl b/components/script/dom/webidls/XRRay.webidl
index 748bd085147..b5fd7ed3494 100644
--- a/components/script/dom/webidls/XRRay.webidl
+++ b/components/script/dom/webidls/XRRay.webidl
@@ -13,7 +13,7 @@ dictionary XRRayDirectionInit {
   double w = 0;
 };
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRRay {
   [Throws] constructor(optional DOMPointInit origin = {}, optional XRRayDirectionInit direction = {});
   [Throws] constructor(XRRigidTransform transform);
diff --git a/components/script/dom/webidls/XRReferenceSpace.webidl b/components/script/dom/webidls/XRReferenceSpace.webidl
index ad9bd41659c..aad31702f01 100644
--- a/components/script/dom/webidls/XRReferenceSpace.webidl
+++ b/components/script/dom/webidls/XRReferenceSpace.webidl
@@ -14,7 +14,7 @@ enum XRReferenceSpaceType {
   "unbounded"
 };
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRReferenceSpace : XRSpace {
   [NewObject] XRReferenceSpace getOffsetReferenceSpace(XRRigidTransform originOffset);
 
diff --git a/components/script/dom/webidls/XRReferenceSpaceEvent.webidl b/components/script/dom/webidls/XRReferenceSpaceEvent.webidl
index a15e7aba316..b9075294d1e 100644
--- a/components/script/dom/webidls/XRReferenceSpaceEvent.webidl
+++ b/components/script/dom/webidls/XRReferenceSpaceEvent.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrreferencespaceevent-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRReferenceSpaceEvent : Event {
   [Throws] constructor(DOMString type, XRReferenceSpaceEventInit eventInitDict);
   [SameObject] readonly attribute XRReferenceSpace referenceSpace;
diff --git a/components/script/dom/webidls/XRRenderState.webidl b/components/script/dom/webidls/XRRenderState.webidl
index d02ab20646a..ff91e0d2fea 100644
--- a/components/script/dom/webidls/XRRenderState.webidl
+++ b/components/script/dom/webidls/XRRenderState.webidl
@@ -14,7 +14,7 @@ dictionary XRRenderStateInit {
   sequence<XRLayer>? layers;
 };
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"] interface XRRenderState {
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"] interface XRRenderState {
   readonly attribute double depthNear;
   readonly attribute double depthFar;
   readonly attribute double? inlineVerticalFieldOfView;
diff --git a/components/script/dom/webidls/XRRigidTransform.webidl b/components/script/dom/webidls/XRRigidTransform.webidl
index 85fb73509fe..11fbf9615b7 100644
--- a/components/script/dom/webidls/XRRigidTransform.webidl
+++ b/components/script/dom/webidls/XRRigidTransform.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrrigidtransform-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRRigidTransform {
   [Throws] constructor(optional DOMPointInit position = {}, optional DOMPointInit orientation = {});
   readonly attribute DOMPointReadOnly position;
diff --git a/components/script/dom/webidls/XRSession.webidl b/components/script/dom/webidls/XRSession.webidl
index a214d6aa133..ccd72b187c6 100644
--- a/components/script/dom/webidls/XRSession.webidl
+++ b/components/script/dom/webidls/XRSession.webidl
@@ -25,7 +25,7 @@ enum XRInteractionMode {
 
 callback XRFrameRequestCallback = undefined (DOMHighResTimeStamp time, XRFrame frame);
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRSession : EventTarget {
   // Attributes
   readonly attribute XRVisibilityState visibilityState;
diff --git a/components/script/dom/webidls/XRSessionEvent.webidl b/components/script/dom/webidls/XRSessionEvent.webidl
index 19ddd9e1b95..4e48f0c6c5c 100644
--- a/components/script/dom/webidls/XRSessionEvent.webidl
+++ b/components/script/dom/webidls/XRSessionEvent.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrsessionevent-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRSessionEvent : Event {
   [Throws] constructor(DOMString type, XRSessionEventInit eventInitDict);
   [SameObject] readonly attribute XRSession session;
diff --git a/components/script/dom/webidls/XRSpace.webidl b/components/script/dom/webidls/XRSpace.webidl
index 3f85f4e4a52..236c9164402 100644
--- a/components/script/dom/webidls/XRSpace.webidl
+++ b/components/script/dom/webidls/XRSpace.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrspace-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRSpace : EventTarget {
   // XRRigidTransform? getTransformTo(XRSpace other);
 };
diff --git a/components/script/dom/webidls/XRSubImage.webidl b/components/script/dom/webidls/XRSubImage.webidl
index 109ee39513b..3e8efdb24d7 100644
--- a/components/script/dom/webidls/XRSubImage.webidl
+++ b/components/script/dom/webidls/XRSubImage.webidl
@@ -5,7 +5,7 @@
 // skip-unless CARGO_FEATURE_WEBXR
 
 // https://immersive-web.github.io/layers/#xrsubimagetype
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRSubImage {
   [SameObject] readonly attribute XRViewport viewport;
 };
diff --git a/components/script/dom/webidls/XRSystem.webidl b/components/script/dom/webidls/XRSystem.webidl
index 41682865cd4..ef5537ebdac 100644
--- a/components/script/dom/webidls/XRSystem.webidl
+++ b/components/script/dom/webidls/XRSystem.webidl
@@ -5,7 +5,7 @@
 // skip-unless CARGO_FEATURE_WEBXR
 
 // https://immersive-web.github.io/webxr/#xrsystem-interface
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRSystem: EventTarget {
   // Methods
   Promise<boolean> isSessionSupported(XRSessionMode mode);
@@ -17,7 +17,7 @@ interface XRSystem: EventTarget {
 
 [SecureContext]
 partial interface Navigator {
-  [SameObject, Pref="dom.webxr.enabled"] readonly attribute XRSystem xr;
+  [SameObject, Pref="dom_webxr_enabled"] readonly attribute XRSystem xr;
 };
 
 enum XRSessionMode {
@@ -33,5 +33,5 @@ dictionary XRSessionInit {
 
 partial interface XRSystem {
   // https://github.com/immersive-web/webxr-test-api/
-  [SameObject, Pref="dom.webxr.test"] readonly attribute XRTest test;
+  [SameObject, Pref="dom_webxr_test"] readonly attribute XRTest test;
 };
diff --git a/components/script/dom/webidls/XRTest.webidl b/components/script/dom/webidls/XRTest.webidl
index 2421f873976..710d3520249 100644
--- a/components/script/dom/webidls/XRTest.webidl
+++ b/components/script/dom/webidls/XRTest.webidl
@@ -6,7 +6,7 @@
 
 // https://github.com/immersive-web/webxr-test-api/
 
-[Exposed=Window, Pref="dom.webxr.test"]
+[Exposed=Window, Pref="dom_webxr_test"]
 interface XRTest {
   // Simulates connecting a device to the system.
   // Used to instantiate a fake device for use in tests.
diff --git a/components/script/dom/webidls/XRView.webidl b/components/script/dom/webidls/XRView.webidl
index 2050afe028a..235eb5a6b2b 100644
--- a/components/script/dom/webidls/XRView.webidl
+++ b/components/script/dom/webidls/XRView.webidl
@@ -12,7 +12,7 @@ enum XREye {
   "none",
 };
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRView {
   readonly attribute XREye eye;
   readonly attribute Float32Array projectionMatrix;
diff --git a/components/script/dom/webidls/XRViewerPose.webidl b/components/script/dom/webidls/XRViewerPose.webidl
index 06274c3dfeb..82f57571f8f 100644
--- a/components/script/dom/webidls/XRViewerPose.webidl
+++ b/components/script/dom/webidls/XRViewerPose.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrviewerpose-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRViewerPose : XRPose {
   // readonly attribute FrozenArray<XRView> views;
   // workaround until we have FrozenArray
diff --git a/components/script/dom/webidls/XRViewport.webidl b/components/script/dom/webidls/XRViewport.webidl
index 079c2d11e2d..4fc6c7afd86 100644
--- a/components/script/dom/webidls/XRViewport.webidl
+++ b/components/script/dom/webidls/XRViewport.webidl
@@ -6,7 +6,7 @@
 
 // https://immersive-web.github.io/webxr/#xrviewport-interface
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRViewport {
   readonly attribute long x;
   readonly attribute long y;
diff --git a/components/script/dom/webidls/XRWebGLBinding.webidl b/components/script/dom/webidls/XRWebGLBinding.webidl
index 5bcb4b381fa..121c2c1db86 100644
--- a/components/script/dom/webidls/XRWebGLBinding.webidl
+++ b/components/script/dom/webidls/XRWebGLBinding.webidl
@@ -5,7 +5,7 @@
 // skip-unless CARGO_FEATURE_WEBXR
 
 // https://immersive-web.github.io/layers/#XRWebGLBindingtype
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRWebGLBinding {
   [Throws] constructor(XRSession session, XRWebGLRenderingContext context);
 
diff --git a/components/script/dom/webidls/XRWebGLLayer.webidl b/components/script/dom/webidls/XRWebGLLayer.webidl
index c3bd54b3d03..e69033fcd2a 100644
--- a/components/script/dom/webidls/XRWebGLLayer.webidl
+++ b/components/script/dom/webidls/XRWebGLLayer.webidl
@@ -18,7 +18,7 @@ dictionary XRWebGLLayerInit {
   double framebufferScaleFactor = 1.0;
 };
 
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_enabled"]
 interface XRWebGLLayer: XRLayer {
   [Throws] constructor(XRSession session,
               XRWebGLRenderingContext context,
@@ -40,5 +40,5 @@ interface XRWebGLLayer: XRLayer {
 };
 
 partial interface mixin WebGLRenderingContextBase {
-    [Pref="dom.webxr.enabled"] Promise<undefined> makeXRCompatible();
+    [Pref="dom_webxr_enabled"] Promise<undefined> makeXRCompatible();
 };
diff --git a/components/script/dom/webidls/XRWebGLSubImage.webidl b/components/script/dom/webidls/XRWebGLSubImage.webidl
index d93f12ff4c5..83ccdd91166 100644
--- a/components/script/dom/webidls/XRWebGLSubImage.webidl
+++ b/components/script/dom/webidls/XRWebGLSubImage.webidl
@@ -5,7 +5,7 @@
 // skip-unless CARGO_FEATURE_WEBXR
 
 // https://immersive-web.github.io/layers/#xrwebglsubimagetype
-[SecureContext, Exposed=Window, Pref="dom.webxr.layers.enabled"]
+[SecureContext, Exposed=Window, Pref="dom_webxr_layers_enabled"]
 interface XRWebGLSubImage : XRSubImage {
   [SameObject] readonly attribute WebGLTexture colorTexture;
   [SameObject] readonly attribute WebGLTexture? depthStencilTexture;