Bug 1704875 - For now, keep synthesizing events on menus if a mouse button is set. r=robwu

This capability is used by browser_ext_menus_capture_secondary_click.js, which
checks that the mouse button is correctly propagated when clicking menu items.
Once bug 1704879 is fixed and activateItem supports specifying a mouse button,
we can revert this patch again.

Differential Revision: https://phabricator.services.mozilla.com/D111901

browser/components/extensions/test/browser/head.js

@@ -509,7 +509,12 @@ async function closeExtensionContextMenu(itemToSelect, modifiers = {}) {
     "popuphidden"
   );
   if (itemToSelect) {
-    itemToSelect.closest("menupopup").activateItem(itemToSelect, modifiers);
+    if ("button" in modifiers) {
+      // Bug 1704879: activateItem does not currently support button
+      EventUtils.synthesizeMouseAtCenter(itemToSelect, modifiers);
+    } else {
+      itemToSelect.closest("menupopup").activateItem(itemToSelect, modifiers);
+    }
   } else {
     contentAreaContextMenu.hidePopup();
   }