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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
/**
* Bugs 1881922, 1901780 - Disable legacy DOM Mutation Events to prevent performance issues.
*/
/* globals exportFunction */
let bug = "1881922";
if (location.origin.includes("vanbreda")) {
bug = "1901780";
}
console.info(
`DOM Mutation Events have been disabled to prevent performance issues. See https://bugzilla.mozilla.org/show_bug.cgi?id=${bug} for details.`
);
(function disableMutationEvents() {
const whichEvents = [
"domattrmodified",
"domcharacterdatamodified",
"domnodeinserted",
"domnodeinsertedintodocument",
"domnoderemoved",
"domnoderemovedfromdocument",
"domsubtreemodified",
];
const { prototype } = window.wrappedJSObject.EventTarget;
const { addEventListener } = prototype;
Object.defineProperty(prototype, "addEventListener", {
value: exportFunction(function (_type, b, c, d) {
const type = _type?.toLowerCase();
if (whichEvents.includes(type)) {
return undefined;
}
return addEventListener.call(this, type, b, c, d);
}, window),
});
})();