Sorry for the late reply. I didn’t get notified of new messages.
I found these bug reports on Bugzilla:
- https://bugzilla.mozilla.org/show_bug.cgi?id=1835322
- https://bugzilla.mozilla.org/show_bug.cgi?id=1843647
- https://bugzilla.mozilla.org/show_bug.cgi?id=1845249
At a quick glance these seem to be the same issue you noticed.
I get the same errors about descriptor, but no mention of mlt or missing libraries.
I tried the flatpak version and that seems to be working.