1. Navigate to https://www.facebook.com/ 2. Tap the enlarge button on a video 3. Attempt to scroll
<rdar://problem/51376074>
Created attachment 372755 [details] patch
Created attachment 372757 [details] patch
Created attachment 372758 [details] patch
Comment on attachment 372758 [details] patch View in context: https://bugs.webkit.org/attachment.cgi?id=372758&action=review > Source/WebKit/ChangeLog:11 > + Scrollable content on the page consists is in overflow scrollers, the main frame is not scrollable. However we still enable > + vertical rubberbanding in the main frame. > + Is the main frame not overflow:hidden in this case (which should disable scrolling)? > Source/WebKit/ChangeLog:14 > + other scrollers don't receive swipes, further attempts just keep the main view in in rubberbanding state. This > + makes scrolling feel glitchy (rubberbanding is only observable in the scrollbar since no content moves). This is really a UIKit bug (44777596). > Source/WebKit/ChangeLog:17 > + This patch disables rubberbanding in non-scrollable main frame if it contains a scrollable element that covers at least > + 50% of the view. That seems pretty likely to break legitimate cases. Also, you don't seem to be only disabling bouncing when the main frame is not scrollable.
Comment on attachment 372758 [details] patch Attachment 372758 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: https://webkit-queues.webkit.org/results/12562733 New failing tests: fast/scrolling/ios/reconcile-layer-position-recursive.html
Created attachment 372767 [details] Archive of layout-test-results from ews124 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews124 Port: ios-simulator-wk2 Platform: Mac OS X 10.14.5
> Is the main frame not overflow:hidden in this case (which should disable > scrolling)? No. > This is really a UIKit bug (44777596). Could well be. This [atch would fix the issue from our side in many cases though. > That seems pretty likely to break legitimate cases. What sort of cases? It is pretty limited. > Also, you don't seem to be only disabling bouncing when the main frame is not scrollable. 'alwaysBounceVertical = NO' is the default behaviour where the scrollview only rubber bands if it has scrollable content.