Tests such as imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-back-forward-cross-doc.html fail. Cross document navigations need to clear the entries.
<rdar://problem/123980334>
It seems to be not WK1 specific - this test fails in both WK2 and WK1 on Minibrowser (WebKit ToT - 276990@main) via WPT.FYI: Live Link - http://wpt.live/navigation-api/currententrychange-event/navigation-back-forward-cross-doc.html