Bug 255324

Summary: Screen sharing stream is always forced to 1920x1080 with letterboxing regardless of the source size
Product: WebKit Reporter: Alexander Khovansky <alex>
Component: WebRTCAssignee: Nobody <webkit-unassigned>
Status: RESOLVED CONFIGURATION CHANGED    
Severity: Normal CC: burzomirdev, eric.carlson, jer.noble, phil917, webkit-bug-importer, youennf
Priority: P2 Keywords: InRadar
Version: Safari 16   
Hardware: Mac (Apple Silicon)   
OS: macOS 13   
Attachments:
Description Flags
Attempting to share a terminal window none

Description Alexander Khovansky 2023-04-12 00:00:26 PDT 
Created attachment 465861 [details]
Attempting to share a terminal window

Minimal reproduction: https://codepen.io/alx-khovansky/pen/MWPgBZG

This pen just requests `getDisplayMedia()` without any constraints and displays the output as well as reports the acquired track settings and capabilities (where supported).

Press `start` and select a non-16:9 surface to share. A window is probably the easiest but a non-16:9 screen would work too. For example, a 14-inch MacBook Pro.

Expected:
A video that matches the dimensions of the shared window.

Actual:
A video that has a 1920x1080 resolution regardless of the source dimensions and has a black area on one of the sides.

Note: the reported track capabilities contain the actual window resolution.
Another observation: past certain size the stream will have black borders on both sides.
Comment 1 Radar WebKit Bug Importer 2023-04-19 00:01:22 PDT 
<rdar://problem/108245927>
Comment 2 burzomirdev 2023-10-11 02:43:23 PDT 
This didn't happen for me in Safari 16 but started in Safari 17. I'd say it was introduced with the new screen sharing menu in Mac OS toolbar.
Comment 3 phil917 2024-02-22 18:08:44 PST 
I just came across this after opening a similar ticket related to this issue and some other getDisplayMedia() issues: https://bugs.webkit.org/show_bug.cgi?id=269961

Like comment 2 mentioned, this seems to be a relatively new issue. The new screen sharing menu in the macOS toolbar has honestly just been an unmitigated disaster in terms of buggy behavior. I have nothing but bad things to say about it from a user experience and technical issues perspective.
Comment 4 Eric Carlson 2024-03-07 09:19:38 PST 
Youenn fixed this with his changes for bug 269961