Bug 227066

Summary: Touch events lost in bottom 10% to 20% of screen when rapidly tapping
Product: WebKit Reporter: Steven Yau <syau>
Component: UI EventsAssignee: Nobody <webkit-unassigned>
Status: NEW    
Severity: Normal CC: graouts, thorton, webkit-bug-importer, wenson_hsieh
Priority: P2 Keywords: InRadar
Version: Safari 14   
Hardware: iPhone / iPad   
OS: iOS 14   
Attachments:
Description Flags
Video of touch events being lost none

Steven Yau
Reported 2021-06-16 07:09:16 PDT
Example: https://yaustar.github.io/ios-touch-issue.html Source: https://github.com/yaustar/yaustar.github.io/blob/master/ios-touch-issue.html The text at the top shows the number of changed touches, the id of the first changed touch in the event, the X / Y position of the first changed touch in the event. Touching the left side of the screen makes it go white, the right, red When rapid tapping the left and right of the screen (0.5s between each touch) in middle or top (portrait), the screen will flip between white and red. When doing the same at the bottom 10% or 20% of the screen, some touches are lost so the screen stays white or red. Is there some extra logic happening at the bottom 10/20% of the screen?
Attachments
Video of touch events being lost (27.76 MB, video/mp4)
2021-06-16 07:34 PDT, Steven Yau 		no flags
Details
View All Add attachment proposed patch, testcase, etc.
Steven Yau
Comment 1 2021-06-16 07:34:03 PDT
Created attachment 431544 [details] Video of touch events being lost This video shows me tapping the screen left/right on the bottom section of the screen where the screen stays white or red despite multiple taps. When tapping the middle, the colours swap as expected.
Radar WebKit Bug Importer
Comment 2 2021-06-23 07:10:24 PDT
<rdar://problem/79664690>
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