"use strict"; add_task(async function () { let tab1 = BrowserTestUtils.addTab( gBrowser, "data:text/plain;charset=utf-8,foo" ); gBrowser.pinTab(tab1); await promiseBrowserLoaded(tab1.linkedBrowser); let tab2 = BrowserTestUtils.addTab(gBrowser); gBrowser.pinTab(tab2); is( Array.prototype.indexOf.call(gBrowser.tabs, tab1), 0, "pinned tab 1 is at the first position" ); await promiseRemoveTabAndSessionState(tab1); tab1 = undoCloseTab(); ok(tab1.pinned, "pinned tab 1 has been restored as a pinned tab"); is( Array.prototype.indexOf.call(gBrowser.tabs, tab1), 0, "pinned tab 1 has been restored to the first position" ); BrowserTestUtils.removeTab(tab1); BrowserTestUtils.removeTab(tab2); });