Your system is broken, FF has supported h265 on every OS for a long time now:
>Firefox enables HEVC on:
>Windows from Firefox 134 using either hardware (on devices that support it, where the range is the same as Edge) or software (on Windows the user must pay for and install an extension)
>macOS from Firefox 136 using either hardware or software.
>Linux from Firefox 137 using either hardware or software (via the system ffmpeg).
>Android from Firefox 137 using hardware only.
https://developer.mozilla.org/en-US/docs/Web/Media/Guides/Fo...
...and even if this wasn't the case, FF has 2.5% market share. Using a 20 year old codec for 2.5% would be insane. If anything, he should be using a newer codec like AV1 that's also widely supported.
> If anything, he should be using a newer codec like AV1 that's also widely supported.
I don't think that's accurate, since the first Apple processors with AV1 support only came out in late 2023 (A17 Pro, M3).
> Using a 20 year old codec for 2.5% would be insane.
Surprisingly, in my experience h264 produces higher quality (better VMAF) for the same bitrate.
My theory is all the codec-optimisation attention went to h264 because of the crazy licensing situation of h265