Bug 254985

Summary: [GTK] YouTube player -- "Scroll for more details" stutters and uses unreasonably much CPU
Product: WebKit Reporter: Kdwk <kdwkleung>
Component: WebKitGTKAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: aperez, bugs-noreply
Priority: P2    
Version: WebKit Nightly Build   
Hardware: PC   
OS: Linux   
Bug Depends on:    
Bug Blocks: 245783    

Description Kdwk 2023-04-04 03:22:33 PDT 
1. Go to YouTube
2. Play a video
3. Fullscreen
4. Scroll down to the comments section from the fullscreen player
5. Observe heavy stutter and intense CPU usage
6. Exit fullscreen
7. Scroll down to comments section
8. No such problem

Tested on WebKitGTK 2.41.1, Epiphany Technology Preview
Comment 1 Kdwk 2023-04-04 03:32:13 PDT 
Scrolling in 'scroll for more details' mode uses about 18-20% CPU, and it simply never comes back down from there, even if the user scrolls back up to the video. The video occasionally stutters. It should be noted that this is even higher than CPU decoding the video (about 13% CPU). The only way to resolve this issue is to close the tab/ web app.
Comment 2 Kdwk 2023-04-20 05:57:13 PDT 
This can now be observed in Gnome Web 44.1/ WebKitGTK 2.40.1