Bug 263706

Summary: HLS Stream Skips Forward When Resumed After Tab is Backgrounded
Product: WebKit Reporter: zhenyi
Component: MediaAssignee: Nobody <webkit-unassigned>
Status: RESOLVED WORKSFORME    
Severity: Normal CC: eric.carlson, jer.noble, smoley, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: Safari 17   
Hardware: Mac (Apple Silicon)   
OS: macOS 14   
Attachments:
Description Flags
Video demonstration of issue. none

Description zhenyi 2023-10-25 20:59:18 PDT 
Created attachment 468344 [details]
Video demonstration of issue.

When a <video> element playing an HLS stream is paused, and the tab is then backgrounded for a period of time (e.g., 5 minutes), upon resuming the video, it skips forward instead of continuing from the paused point.

Steps to Reproduce:
1. Navigate to https://andadinosaur.com/hls-test in Safari.
2. Play the video.
3. Pause the video.
4. Open a new tab (this backgrounds the tab with the video).
5. Wait for 5 minutes.
6. Return to the original tab with the video.
7. Resume the video.

Expected Results: The video should resume from the point where it was paused.

Actual Results: The video skips forward when resumed.
Comment 1 Radar WebKit Bug Importer 2023-10-26 13:19:58 PDT 
<rdar://problem/117548456>
Comment 2 Smoley 2024-01-23 12:41:55 PST 
This does not reproduce for me on STP186. Are you still able to reproduce this on latest Safari Technology Preview? https://developer.apple.com/safari/download/

Thanks!