Well, deleting the .wp-toolkit-ignore (can be done in the file manager) solves the issue.
It might be an idea to update the Plesk documentation to give a heads-up to new users.
I will leave this answer for anyone in the same situation.
If a moderator sees this as suitable, he could mark this...
Dear All
I encountered the following issue.
While cleaning up the WP Toolkit, I detached the wrong website.
According to the Plesk documentation, pressing "scan" should redisplay my website.
However, this doesn't work and I can't find it anymore.
The website runs without issues and I can edit...