If you've installed the Firefox browser using flatpak on openSUSE, you probably have noticed these two issues:

  • poor video quality with lags (e.g videos on Twitter)
  • funky font display on some pages (e.g Facebook)

Firefox comes with the ffmpeg extension enabled but the libs need to be installed. At the time of writing this post, the extension for ffmpeg version 20.08 was enabled in the following file if you installed Firefox using the --user flag with Flatpak.


The file should have something like this:

[Extension org.freedesktop.Platform.ffmpeg-full]

Therefore, you can install ffmpeg version 20.08.

flatpak install org.freedesktop.Platform.ffmpeg-full/x86_64/20.08 --user

If you do not provide the /x86_64/20.08 path then Flatpak will ask you to confirm which version to install and provide you a list of available versions. At the moment, versions 19.08, 20.08 and 21.08 are available. The videos work fine with ffmpeg version 20.08 for me.

If you installed Firefox system-wide, then you should find the extension metadata in the /var/lib/flatpak/app ... location instead of the ~/.local/share/flatpak/app ... directory.

The bug has been discussed within Mozilla.

Next, to fix the funky or chunky font in some webpages, I found the following suggestion through Mozilla bug reports. Add the following text in ~/.var/app/org.mozilla.firefox/config/fontconfig/fonts.conf file.

<?xml version='1.0'?>
<!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
    <!-- Disable bitmap fonts. -->
        <patelt name="scalable"><bool>false</bool></patelt>

Close & re-open Firefox. Font rendering should be better.