One day I found that all the documents I'd edited with the great
StackEdit(https://stackedit.io" markdown editor were gone.
"What can I do? I want them back!" I thought. Then I saw in my desktop an icom
of a folder named "Old Firefox Data".
As a FreeBSD user, I tried running a find command to find matches for
'*StackEdit*' or '*stackedit*' or whatever, in both "~/Desktop" and
It works! Woohoo!
So, I copied a direcory named "https+++stackedit.io" from the path
"g0520kyx.default/storage/default" relative to "~/Desktop/Old\ Firefox\ Data"
to its equivalent under "~/.mozilla/firefox".
This restored my works.
Another thing you can do is use backups, of course.