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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";
/**
*
* If consecutive session history entries had history.state.entryTime set to same value,
* back button doesn't work as expected. The entryTime value is coming from performance.now()
* and modifying its return value slightly to make sure two close consecutive calls don't
* get the same result helped with resolving the issue.
*/
/* globals exportFunction */
console.info(
"performance.now precision has been modified for compatibility reasons. See https://bugzilla.mozilla.org/show_bug.cgi?id=1756970 for details."
);
const origPerf = performance.wrappedJSObject;
const origNow = origPerf.now;
let counter = 0;
let previousVal = 0;
Object.defineProperty(window.performance.wrappedJSObject, "now", {
value: exportFunction(function () {
let originalVal = origNow.call(origPerf);
if (originalVal === previousVal) {
originalVal += 0.00000003 * ++counter;
} else {
previousVal = originalVal;
counter = 0;
}
return originalVal;
}, window),
});