Today I have managed to fuck up my entire osu! Lazer install just by running one command.
ln -s /path/to/external/osu/folder ~/.local/share/osu
For some fucking reason this will mess with your install and delete your collections and either delete or fuck all your maps back to 0 stars. It also changed my game language to German for some reason? This is entirely my fault for listening to a Reddit comment by Peppy 6 years ago that was for a Windows user.
This was entirely my fault as the osu! folder has a huge README in multiple folders that warns you to not do stupid shit. I should have also made a backup before doing something like this. Hopefully this appears in someones search engine before someone else tries this.
If I just checked the settings menu for 2 seconds I would have noticed the HUGE "Change Directory" button and I would have been fine. Now I have to redo all my collections but luckily I only wanted to move osu! to my bigger drive just so I can have enough space to install all ranked + loved maps.
Hopefully you find this useful or at least kinda funny.