I would like to start and use Firefox with the command MOZ_X11_EGL=1 without having to type MOZ_X11_EGL=1 firefox into the terminal each and every time (I use the command in order to enable vaapi video acceleration on X11).

  • How can I edit the existing Firefox shortcut in order to add MOZ_X11_EGL=1 ?
  • How can I create a completely new shortcut with MOZ_X11_EGL=1 ?

OS: Ubuntu 20.10, using the preinstalled Firefox version that shipped with Ubuntu.


To edit the existing shortcut, copy the desktop file of Firefox from /usr/share/applications (firefox) to the folder .local/share/applications in the home folder. Edit the Exec= line.

If more users need to be able to use that launcher, place a copy of the .desktop file in a /usr/local/share/applications folder. That will override the copy in /usr/share/applications. You could edit the original launcher directly, but it might be overwritten by a future update.

  • Hi, thanks for helping out. I tried adding "MOZ_X11_EGL=1" to the "exec=" line after performing all the necessary steps beforehand, but Firefox still launches normally, without the env MOZ_X11_EGL=1. Could you tell me how exactly the exec line has to look like in order to launch firefox via MOZ_X11_EGL=1 pls? – Oranges86 Nov 13 '20 at 0:29
  • Ok, got it working now. Under "[Desktop Entry]" look for the line "Exec=firefox %u" and replace it with "Exec=env MOZ_X11_EGL=1 firefox %u" (without the quotes ofc). Save the file and launch Firefox normally via the desktop or dash shortcut and voilà - - - Firefox is now using the env MOZ_X11_EGL=1 by default. Thx @vanadium for the help! – Oranges86 Nov 13 '20 at 18:36

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