Steps to reproduce:
Scroll the page by initiating touch gesture from the green background. Page scrolls, this is expected. Scroll until the address bar disappears.
White box has "touch-action: pan-x" applied. Initiate touch gesture from the white box. Page does not scroll, this is expected.
Attempt to scroll down from white box. Page does not scroll but address bar *does* expand. This is not expected.
This breaks non-native drag gesture implementations.
This also happens with (native) horizontal scroll containers.
It would also be great to have a way to prevent this on vertical scroll/pan-y, as it is not always desirable. This library, for instance, is broken because the viewport gets resized as a picture is being swiped up or down: https://photoswipe.com
This is controlled by MobileSafari code. The above radar tracks that issue.
I recently ran into this issue as well. In case more info is required, here's a Stack Overflow question:
Also a reproduction site:
And a demo video of the problem:
This is being addressed within Safari, not WebKit.
We believe that this bug was fixed in the iOS 16.0 Beta 1 (and newer).