Crashtracer inside PDFPlugin::createScrollbar. Yet again after https://trac.webkit.org/changeset/266756/webkit We know more this time: A PDFPlugin might try to install a PDFDocument after the plugin owner element has been destroyed.
rdar://problem/69256031
Created attachment 409333 [details] Patch
Committed r267412: <https://trac.webkit.org/changeset/267412> All reviewed patches have been landed. Closing bug and clearing flags on attachment 409333 [details].