Thunderbird (Flathub)

org.mozilla.Thunderbird (aka net.thunderbird.Thunderbird)

Thunderbird for Flatpak installation instructions are available by clicking here to visit the Thunderbird app page on Flathub.

Known issues:

Non flatpak-packaging issues should be reported upstream at
https://bugzilla.mozilla.org/describecomponents.cgi?product=Thunderbird

Migration from pre-exisiting non-flatpak installations

In order to migrate from pre-exisiting non-flatpak installation and preserve all settings please copy or move entire
~/.thunderbird
folder into
~/.var/app/org.mozilla.Thunderbird/.thunderbird

In case Thunderbird opens a new profile instead of the existing one, run:
flatpak run org.mozilla.Thunderbird -P
then select the right profile and tick "Use the selected profile without asking on startup" box.

Language support

(#3) All supported locales are available in org.mozilla.Thunderbird.Locale extension. One locale that matches host OS locale will be installed and selected by default. For instructions about how to enable more locales in flatpak take a look at https://flatpak.readthedocs.io/en/latest/flatpak-command-reference.html#flatpak-config

(#90) Dictionaries availability is similar as for locales. They also could be downloaded manually from:
https://addons.thunderbird.net/language-tools/
and installed through:
Menu Bar > Tools > Add-ons > Extensions > Install Add-on From File
You may need to restart app in order to make changes effective.

New mail notifications

(#11) To enable new mail notifications:

1. Menu Bar > Edit > Preferences > Advanced > General > Config Editor…, set mail.biff.use_system_alert to true (default)
   
2. Menu Bar > Edit > Preferences > General > Select Customize… for "Show an alert" and set "Show New Mail alert for:"

(#79) Alternatively you may set mail.biff.use_system_alert to false which will make notifications non-native but clicking on them will open mail in Thunderbird.

Wayland

(#75) To enable the experimental Wayland backend (assuming the desktop session runs under a Wayland) set:
flatpak override --user --env=MOZ_ENABLE_WAYLAND=1 org.mozilla.Thunderbird

Smartcard

(#51) For Smartcard support you need at least Flatpak 1.3.2.

Other flatpak issues unresolved yet by upstream

(#123) Opening Profile Directory doesn't work: https://bugzilla.mozilla.org/show_bug.cgi?id=1625111