Snap packages are not improved.

[dumol]

It seems that Snap packages can't access hidden sub-directories from $HOME. This is especially a problem for latest Ubuntu releases, where Firefox is a Snap package that can only access non-hidden files and sub-directories from a user's home directory.

[dumol]

A solution for Ubuntu's Firefox inspired by https://askubuntu.com/a/1460014:

ln -s ~/.local/share/fonts ~/snap/firefox/current/.local/share/fonts
mv ~/snap/firefox/current/.config/fontconfig ~/snap/firefox/current/.config/fontconfig.orig
ln -s ~/.config/fontconfig ~/snap/firefox/current/.config/fontconfig
fc-cache -f -r

After running the above commands, restart Firefox.

[dumol]

Documented through 06bfc73.

Upstream issue: https://bugzilla.mozilla.org/show_bug.cgi?id=1760996.