Bug 255914

Summary: REGRESSION (Safari 16.4): Dynamically set `<meter>` doesn't show the value
Product: WebKit Reporter: Thomas Steiner <tomac>
Component: New BugsAssignee: Aditya Keerthi <akeerthi>
Status: RESOLVED FIXED    
Severity: Normal CC: akeerthi, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: Safari 16   
Hardware: Mac (Apple Silicon)   
OS: macOS 13   
Attachments:
Description Flags
Safari
none
reduction none

Description Thomas Steiner 2023-04-25 01:33:15 PDT 
Created attachment 466071 [details]
Safari

1. Go to https://like-spiffy-pick.glitch.me/ on Safari Version 16.5 (18615.2.5.11.2) or Safari Technology Preview Release 168 (Safari 16.4, WebKit 18616.1.10.2) on macOS 13.4 Beta (22F5037d).
2. Notice how the first `<meter>`'s value isn't shown.
3. Try the same on Chrome, all three `<meter>`s' values are shown.

The fix is to hide, then show the `<meter>`, or to populate the attributes statically, which may or may not be an option. This affects https://howfuguismybrowser.dev/.
Comment 1 Thomas Steiner 2023-04-25 01:34:21 PDT 
In my tests, this seems to only affect desktop Safari, it works fine on iOS.
Comment 2 Thomas Steiner 2023-04-25 01:39:32 PDT 
See the screenshot for details: https://bugs.webkit.org/attachment.cgi?id=466071.
Comment 3 Anne van Kesteren 2023-04-25 02:37:53 PDT 
Aditya, can you take a look?
Comment 4 Radar WebKit Bug Importer 2023-04-25 02:38:07 PDT 
<rdar://problem/108495001>
Comment 5 Aditya Keerthi 2023-04-25 11:00:48 PDT 
I'm unable to reproduce on https://like-spiffy-pick.glitch.me/, but can reproduce on https://howfuguismybrowser.dev/.
Comment 6 Aditya Keerthi 2023-04-25 12:40:24 PDT 
Created attachment 466080 [details]
reduction

Attaching a reliable reproduction.
Comment 7 Aditya Keerthi 2023-04-25 15:49:33 PDT 
Confirmed this is a regression in Safari 16.4.

This also reproduces with <progress>, and is fallout from GPU Process refactoring work. We need to ensure our `ControlPart` state is up-to-date, probably in `RenderBox::ensureControlPart`.
Comment 8 Aditya Keerthi 2023-04-26 17:33:18 PDT 
Pull request: https://github.com/WebKit/WebKit/pull/13218
Comment 9 EWS 2023-04-27 16:57:42 PDT 
Committed 263473@main (340e63b309b7): <https://commits.webkit.org/263473@main>

Reviewed commits have been landed. Closing PR #13218 and removing active labels.