If the app is creating the Web process pool after being activated, preferences will not be observed until the app is being backgrounded and then foregrounded again, since the preference observer is initialized when handling the app activation notification.
rdar://problem/63720477
Created attachment 401774 [details] Patch
Created attachment 401778 [details] Patch
Comment on attachment 401778 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=401778&action=review r=me > Source/WebKit/UIProcess/Cocoa/WebProcessPoolCocoa.mm:474 > + startObservingPreferenceChanges(); Do we need to do anything special to stop observing preferences in this case? Or is it handled automatically by the normal code paths?
Created attachment 401782 [details] Patch
Created attachment 401783 [details] Patch
(In reply to Brent Fulgham from comment #4) > Comment on attachment 401778 [details] > Patch > > View in context: > https://bugs.webkit.org/attachment.cgi?id=401778&action=review > > r=me > > > Source/WebKit/UIProcess/Cocoa/WebProcessPoolCocoa.mm:474 > > + startObservingPreferenceChanges(); > > Do we need to do anything special to stop observing preferences in this > case? Or is it handled automatically by the normal code paths? Actually, we will observe preference changes during the full lifetime of the UI process. Thanks for reviewing!
Committed r262984: <https://trac.webkit.org/changeset/262984> All reviewed patches have been landed. Closing bug and clearing flags on attachment 401782 [details].