add_task(function* () { yield new Promise(resolve => { SpecialPowers.pushPrefEnv({"set": [["browser.autofocus", false]]}, resolve); }); const url = "data:text/html,"; let loadedPromise = BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser); gBrowser.selectedBrowser.loadURI(url); yield loadedPromise; yield new Promise(resolve => executeSoon(resolve)); yield ContentTask.spawn(gBrowser.selectedBrowser, null, function* () { is(content.document.activeElement, content.document.body, "body focused"); }); });