Linux Mint 21.3 Login Window users list hidden, no way to log in

[noreasternhumidity]

slick-greeter 2.0.3
Linux Mint 21.3
Intel embedded video Mesa 3000 (test computer)
64 bit

Issue

When "Guest Account" is activated and also "Hide The User List" is enabled in Login Window app, the user list will not be accessible to the Administrative (or maybe even Standard) user who is trying to log back in.

Steps to reproduce
Activate Guest Account and also enable "Hide The User List", log in and use Guest account at least once, then reboot.

Expected behaviour
With "Hide The User List" enabled, the Username and then the Password inputs boxes should be available.

Other information
I was able to reproduce this on a test machine, based on another's problem report.