Bug 214726

Summary:	scroll-snap jumpy with playing video content
Product:	WebKit	Reporter:	Ben Ubois <ben>
Component:	Scrolling	Assignee:	Nobody <webkit-unassigned>
Status:	NEW ---
Severity:	Normal	CC:	jer.noble, mrobinson, simon.fraser, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	Other
Hardware:	iPhone / iPad
OS:	Other

Description Ben Ubois 2020-07-24 02:14:46 PDT

Overview
--------

Scrolling is jumpy when playing a video inside of a container that uses `scroll-snap`. 


Steps to Reproduce
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1. Visit https://codepen.io/asdf/full/WNrmdPK
2. Play the video
3. Scroll to the right and left repeatedly 


Actual Results
--------------

Scrolling appears to jump around with significant jank.


Expected Results
----------------

Scrolling is smooth


Build Date & Hardware
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iOS 14 (18A5319i) iPhone and iPad


Additional Builds and Platforms
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- iOS 14 developer beta 1-3
- iOS 14 public beta


Doesn't Occur On 
----------------

- iOS 13 or previous
- Safari Technology Preview Release 110 (Safari 14.0, WebKit 15610.1.21.0.2)


Additional Information
----------------------

Here's a video demonstration: https://www.dropbox.com/s/i1jr4nul4uf15xh/scrolling.mp4?dl=0

Please let me know if there's any more information I can provide.

Thanks!

Comment 1 Radar WebKit Bug Importer 2020-07-24 11:05:58 PDT

<rdar://problem/66063432>

Comment 2 Simon Fraser (smfr) 2020-07-24 11:22:29 PDT

https://trac.webkit.org/changeset/264704/webkit may have fixed this

Comment 3 Martin Robinson 2021-07-07 08:07:55 PDT

I'm not able to reproduce this with the latest from master.