No scroll bar on login menu

[smithwesson]

I have a system with about 20 user accounts. Just upgraded LMDE. There's no scrollbar on the login page showing the account names, so any usernames not at the top of the list are essentially inaccessible. (You can use tab or arrows to go below what's visible on the screen, but you're taking a guess what name you're hitting.)

[phd7]

how about the down arrow?

[smithwesson]

The list of usernames does not scroll when the down arrow hits the bottom-most. The arrow keeps going, but you can't see what it's highlighting.

[smithwesson]

For posterity: solved my own problem by installing SLiM.