add-user ignores desired username

[SimJoSt]

I created a new user using bin/plugin login add-user and entered a username when prompted.
After entering all the other information as well, I got the following success message

Success! User 1 created.

I thought nothing of it, as I just created 1 (one) user. But appearently the user was actually named 1. I had to change the name of the .yml file in the accounts folder.

[mahagr]

As workaround use --user=username parameter until the fix has been released.