You're welcome. I'm glad it helped, at least a little bit
It's strange though, because in Linux, config files are usually stored into your home folder as a hidden file (wild guess,
/home/gravity-1/.thuderbird). That's the file it should be reading from when thunderbird starts... So it does not have much to do with the executable itself, as far as I'm concerned.
Try deleting that hidden file and restart thunderbird to see if that helps.
Good luck!