So you added a user account to your linux (mobile) for any reason? That account will never be used to login to #Linux?

Well, it will show up on your login screen unless you picked an uid from the range of system accounts.

On #Mobian and #postmarketOS the login screen is presented by the greeter run from greetd. For #Phosh the greeter is #Phrog. The user accounts to show on the login screen are requested from #AccountsServices.

One way to get rid of an user account on the login screen is to mark it as a system account: USER=<username>; echo -e '[User]\nSystemAccount=true' | sudo tee /var/lib/AccountsService/users/$USER; sudo chmod 600 /var/lib/AccountsService/users/$USER

https://www.freedesktop.org/wiki/Software/AccountsService https://github.com/samcday/phrog https://sr.ht/~kennylevinsen/greetd/