thunderbird

This is how to handle situation when Thunderbird wants to do set up from scratch after it crashed. First locate profile folder - you can do that in Thunderbird by using Help -> More troubleshooting information. Once you locate this folder looks for prefs.js and possibly prefs-1.js, prefs-2.js etc.

Reason for this is application .desktop file missing MimeType specification. For example for me mplayer and thunderbird are not listed as choices for video and mail respectively. To fix this edit application's .desktop file (in /usr/local/share/applications directory, or in ~/.local/share/applications) and run update-desktop-database afterwards (with -v to show its warnings).

One place to put all little tweaks to make it work better with FreeBSD.