1932392 - VideoDecoder.isConfigSupported() incorrectly reports true

Status: UNCONFIRMED

(Core :: Audio/Video: Web Codecs, defect)

Description

[Pierre Ossman]

Steps to reproduce:

1. git clone https://github.com/novnc/noVNC.git
2. cd noVNC
3. npm install
4. npm test
5. firefox http://localhost:9876

Actual results:

Tests fail with "The given encoding is not supported.".

Expected results:

Tests should succeed, or be skipped.

Comment 1

[Pierre Ossman]

This issue only happens when I install Mozilla's build of Firefox on Ubuntu. It does not happen with Ubuntu's own snap packaging (though, see bug 1932391).

The odd thing is that about:support reports "Unsupported" for H264, but VideoDecoder.isConfigSupported() reports true.

Comment 2

[Pierre Ossman]

Bug 1918769 sounds like the same symptoms.

Comment 3

[Pierre Ossman]

Attachment: Debug log

Comment 4

[Pierre Ossman]

Debug log from a test run attached. Note that it says that all decoders reject the type video/avc, yet it still returns success back to the JavaScript code.

Comment 5

[Pierre Ossman]

Hmm... Something has changed here now. I'm now on Firefox 133 (some issue on nightly as well).

I'm now getting the same symptoms as bug 1932579. Only in "normal" mode, though. Headless still gives me bug 1932391.