Client should be able to disable PSON even if the experimental feature is on by default.
Turning on the experimental feature currently causes ProcessSwap.NavigationWithLockedHistoryWithoutPSON to fail.
Created attachment 354817 [details] Patch
Created attachment 354821 [details] Patch
Comment on attachment 354821 [details] Patch Clearing flags on attachment: 354821 Committed r238183: <https://trac.webkit.org/changeset/238183>
All reviewed patches have been landed. Closing bug.
<rdar://problem/46066512>