const PAGE = ` `; add_setup(async function () { await SpecialPowers.pushPrefEnv({ set: [["test.wait300msAfterTabSwitch", true]], }); }); add_task(async function () { const url = "data:text/html," + encodeURI(PAGE); await BrowserTestUtils.withNewTab({ gBrowser, url }, async function () { let popup = await openSelectPopup("click"); is(popup.children.length, 2, "Both options should appear in the popup"); is(popup.children[0].textContent, "ABC", "First option shows up"); is( popup.children[1].textContent, "DEF", "Option with display:inherit shows up" ); }); });