The tests under imported/w3c/web-platform-tests/html/browsers/browsing-the-web/navigating-across-documents/refresh/* as well as imported/w3c/web-platform-tests/html/browsers/browsing-the-web/navigating-across-documents/redirect-to-about.window.html started failing on both GTK and WPE just around the time that the SOUP version was bumped to 3. Attempting to regress through changelists doesn't seem to work, however, so I don't have an exact point at which these tests regressed.