Similar to https://bugs.webkit.org/show_bug.cgi?id=187720.
"Fullscreen requires the window to be on screen. These tests must put the window on screen before attempting fullscreen."
Created attachment 345164 [details]
Comment on attachment 345164 [details]
Clearing flags on attachment: 345164
Committed r233889: <https://trac.webkit.org/changeset/233889>
All reviewed patches have been landed. Closing bug.