So I had following issue:
I followed all the steps and replaced my old "windowManager.js" with the new one.
Now the whole UI is pretty destroyed in some kind of security mode. It asks me if I want to restart the UI, if I click YES, everything loads up again with the same issue.
I'm pretty sure I failed replacing the "windowManager.js" because I just can't handle the terminal commands yet (I just copypasted the code on the site). Started with Mint 2 Days ago.
Well I tried to use the Backup ("windowManager.js.old") and renamed it with root. Didn't help either. I don't want to reinstall the whole system (I want to learn how to deal with this).
Help is very much appreciated.