- Solved
Firefox will not play video on Linux
Firefox 129.0.2 (64-bit) Mozilla Firefox Snap for Ubuntu canonical-002 - 1.0 Running on kubuntu Linux 24.04, kernel version 6.8.0-41-generic (64-bit) KDE Plasma Versio… (read more)
Firefox 129.0.2 (64-bit) Mozilla Firefox Snap for Ubuntu canonical-002 - 1.0
Running on kubuntu Linux 24.04, kernel version 6.8.0-41-generic (64-bit) KDE Plasma Version 5.27.11 Qt Version 5.15.13
I've posted a description of my problem on the kubuntu forums: https://www.kubuntuforums.net/forum/newbie-support/help-the-new-guy/681835-firefox-eating-up-a-lot-of-cpu
Here is a synopsis of my posts on that thread to distill the most noteworthy symptoms:
I have snap Firefox installed.
$ snap list Name Version Rev Tracking Publisher Notes bare 1.0 5 latest/stable canonical✓ base core22 20240731 1564 latest/stable canonical✓ base firefox 129.0.2-1 4793 latest/stable mozilla✓ - firmware-updater 0+git.5007558 127 latest/stable/… canonical✓ - gnome-42-2204 0+git.510a601 176 latest/stable/… canonical✓ - gtk-common-themes 0.1-81-g442e511 1535 latest/stable/… canonical✓ - snapd 2.63 21759 latest/stable canonical✓ snapd thunderbird 128.1.0esr-1 507 latest/stable/… canonical✓ - $
If I start firefox from the shell command line, it runs fine. It runs the shell script in /usr/bin/firefox, which ultimately executes /snap/bin/firefox. Clearly that shell script is doing some configuration that I don't understand.
If I hit Alt-space I see the menu in the referenced screen grab (see attached).
If I select the first entry, to run firefox from the command line, it has the same effect as starting /usr/bin/firefox from a bash shell; it works fine. However, if I select the third entry, firefox does not play any video; I've mostly tested with YouTube videos that have actual video and audio.
I'm not sure what gets executed when I select the third option from the Alt-space menu. It appears from doing a "ps -ef" that it's the same /snap/firefox/... executable. But I'm wondering why is this entry in the Alt-space menu and how does it get initialized or 'configured' to run.
Additionally, if I do start firefox from the entry with the firefox browser icon, and it fails to play video, I must then uninstall firefox using snap and then reinstall in order to get video playback to work. That is, after a failed start, simply exiting firefox and restarting it from the shell command line will not work; firefox will not play video correctly at all.
I also noticed that on my PC desktop, "snap list" lists firefox as "firefox 129.0.2-1 4793 latest/stable mozilla✓ -"
But on my old Lenova laptop running the same kubuntu version, "snap list" lists firefox as "firefox 129.0.2-1 4757 latest/stable mozilla✓ -"
I'm up to date on both systems via "sudo apt update"' and "sudo apt upgrade"
Even more frustrating, today, for the first time, despite starting firefox from the command line, video still didn't play. I had to uninstall firefox and reinstall it.