Auto merge of #24564 - paulrouget:initButtons, r=jdm

Properly set MouseEvent buttons property

Properly set MouseEvent buttons property. Same behavior as Chrome and Firefox.

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- [x] These changes fix #24363 (GitHub issue number if applicable)

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/script/dom/mouseevent.rs b/components/script/dom/mouseevent.rs
index fc0f777ecd5..48600f1155e 100644
--- a/components/script/dom/mouseevent.rs
+++ b/components/script/dom/mouseevent.rs
@@ -137,7 +137,7 @@ impl MouseEvent {
             init.parent.shiftKey,
             init.parent.metaKey,
             init.button,
-            0,
+            init.buttons,
             init.relatedTarget.as_deref(),
             None,
         );