After fixing webkit.org/b/238667, these tests pass on macOS and iOS, however they continue to fail on GTK.
These tests have been constantly passing in GTK for the last 4000 commits. https://results.webkit.org/?platform=GTK&platform=WPE&platform=mac&platform=ios&suite=layout-tests&test=imported%2Fw3c%2Fweb-platform-tests%2Fcss%2Fcss-contain%2Fcontain-size-select-elem-001.html Closing bug.