Bug 243926

Summary: Closed captions in <video> element breaks long lines to above the previous line instead of under it
Product: WebKit Reporter: zhuowei
Component: MediaAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: eric.carlson, jensimmons, jer.noble, karlcow, webkit-bug-importer
Priority: P2 Keywords: BrowserCompat, InRadar
Version: Safari 15   
Hardware: Mac (Intel)   
OS: macOS 12   
Attachments:
Description Flags
Screenshot of two lines of closed caption displayed in the wrong order. The bottom line of caption should be read before the top line. none

Description zhuowei 2022-08-14 09:35:56 PDT
Created attachment 461619 [details]
Screenshot of two lines of closed caption displayed in the wrong order. The bottom line of caption should be read before the top line.

When playing the video https://www.cartoonnetwork.com/video/unlocked/a-media-episode.html with closed captions enabled, long lines in the closed captions are wrapped into two lines, but the second line is displayed above the first instead of below the first.

Can reproduce in:
- Safari Version 15.6 (17613.3.9.1.5)
- Safari Technology Preview Release 151 (Safari 16.0, WebKit 17615.1.1.2)
both on macOS 12.5 on MacBook Pro (Retina, 13-inch, Early 2015).

Testing in other browsers:
- Chrome (Version 106.0.5231.2 (Official Build) dev (x86_64)) displays the closed captions correctly.
- Safari on iOS 14.1 displays the captions correctly.
- Firefox 103.0.1 (64-bit) breaks lines in the caption correctly (although it incorrectly displays the captions shifted too much to the right).
Comment 1 Radar WebKit Bug Importer 2022-08-21 09:36:15 PDT
<rdar://problem/98947881>