How do I install and migrate to the official Firefox flatpak?

Backing up your existing profile

Before we begin we should always back up our stuff, even if you’re using Firefox Sync

Install Flathub

Mozilla publishes Firefox directly into Flathub, however we need to turn this on in Ubuntu. Follow these instructions, I am summarizing them below:

sudo apt install flatpak
sudo apt install gnome-software-plugin-flatpak
flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo    

Install Firefox

This will install Firefox and the corresponding ffmpeg libraries so videos, etc work:

flatpak install flathub org.mozilla.firefox org.freedesktop.Platform.ffmpeg-full/x86_64/20.08

Then the Firefox icon will appear in your menu/overlay, or you can do firefox run org.mozilla.firefox to launch it from the command line.

Migrating your profile

[todo]

Reusing your old profile

You can also reuse your profile without manually copying it over though this probably isn’t a good permanent solution.

Quit firefox, then do flatpak override --user --filesystem=~/.mozilla org.mozilla.firefox to have the flatpaked Firefox reuse your old profile.

Checking your work

Clicking on the burger menu -> Help -> About Firefox will show “Mozilla Firefox Flatpak” and “mozilla-flatpak” in the dialog window:

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