Thunderbird not saving passwords on Ubuntu 18.04

What worked for was: delete pkcs11.txt in profile

Taken from this: https://support.mozilla.org/nl/questions/1239779

Good luck!

Thanks for your answers and the link above - worked for me!

The file 'pkcs11.txt' contains readable ASCII text and has an absolute path to the profile folder, which does not fit after moving the folder.

This was the case when I moved Thunderbird from Win7 to Linux! I renamed the original file, started Thunderbird again and compared the generated file with the renamed one. The diff tool showed only differences in that absolute path.

Find your profile directory. In default case it name looks like something.default and stored in ~/.thunderbird/. Ok, run ls -lah ~/.thunderbird/ to view directories in ~/.thunderbird/. Then when you found your profile name use:

cd ~/.thunderbird/<replace to your data>.default

and run

sudo rm pkcs11.txt

Restart thunderbird.