Bug 207687

Summary: scrollTop change in pointermove event results flickering
Product: WebKit Reporter: Roland Soos <roland>
Component: ScrollingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: graouts, simon.fraser, thorton, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: Safari 13   
Hardware: All   
OS: All   
Attachments:
Description Flags
Test case
none
Screen record none

Description Roland Soos 2020-02-13 04:37:27 PST
Created attachment 390628 [details]
Test case

Steps to reproduce:
#1 Open https://smartslider3.com/bugs/webkit/pointerscroll/
#2 hold the pointer down and move it up or down

What should happen?
The pointer movement should move the scroll up and down

What went wrong?
During the scrollTop change the screen starts to flicker
Comment 1 Roland Soos 2020-02-13 04:38:05 PST
Created attachment 390629 [details]
Screen record
Comment 2 Radar WebKit Bug Importer 2020-02-16 18:07:52 PST
<rdar://problem/59498307>
Comment 3 Simon Fraser (smfr) 2020-02-17 10:39:01 PST
I can reproduce. Is it better if you use touch events?
Comment 4 Roland Soos 2020-02-17 23:40:29 PST
Simon: It is a little bit better, but from user perspective it is as worse as with the pointer events. The only difference that the Safari top and bottom UI is not flickering.

https://smartslider3.com/bugs/webkit/pointerscroll/touch.html