According to results.webkit.org, these two tests have been consistently flaky since r269567: fast/loader/font-load-timer.html [ ImageOnlyFailure Pass ] imported/w3c/web-platform-tests/html/browsers/browsing-the-web/history-traversal/persisted-user-state-restoration/resume-timer-on-history-back.html [ Failure Pass ] https://results.webkit.org/?suite=layout-tests&suite=layout-tests&test=imported%2Fw3c%2Fweb-platform-tests%2Fhtml%2Fbrowsers%2Fbrowsing-the-web%2Fhistory-traversal%2Fpersisted-user-state-restoration%2Fresume-timer-on-history-back.html&test=imported%2Fw3c%2Fweb-platform-tests%2Fhtml%2Fbrowsers%2Fbrowsing-the-web%2Fhistory-traversal%2Fpersisted-user-state-restoration%2Fresume-timer-on-history-back.html&platform=WPE&platform=GTK I don't understand though how r269567 can be affecting these tests.