Hey, thank you for your answer. I spend the night doing exactly this. after testing everything in a virtual machine again and again. My server is back up. for now. Still don't know what caused the crash... Maybe i should've saved the logs.
Just for the understanding. What does this mean 'ERROR: layer does not exist'? How can I fix this manually?
And, a bit OT, is git stash, git pull and git stash pop really enough? I remember some error but I ignored it. After starting everything, i got an error on my webui because git stash wrote some "<<<<<>>>>" in the header.inc.php
What have I done wrong?