That should just be Electron state so nothing really important, but I'm surprised it's under ~/.config/Joplin. Maybe have a look inside the folder, what's in there?
For context, we moved the Electron state to the "internal" folder because it contains in particular the user dictionary. That way there's just one folder with al the Joplin user settings
If I quit Joplin and delete the ~/.config/Joplin folder, the folder and its contents are recreated at the next app startup (in the screenshot all files / folders have the same modified date). Should this happen if the Electron state has been moved to the ~/.config/joplin-desktop/internal/ folder?
I only found this as in Linux the Markdown editor spellchecker has stopped working and I was trying to work out whether it was my system or Joplin.
Just glancing at the director this morning, I get …
todd@surface:~/.config/Joplin$ ll |grep "May 25"
-rw------- 1 todd todd 16512 May 25 08:51 DIPS-wal
-rw------- 1 todd todd 63371 May 25 07:51 Preferences
-rw------- 1 todd todd 0 May 25 07:53 SharedStorage-wal
drwx------. 1 todd todd 72 May 25 07:51 blob_storage