no login frame after wake from sleep

it happens pretty often (would say every 5-6th time after waking up) that I get no login frame on login screen, but everything else seems fine, what could it be? and ho to get it around so I don’t have to restart?

What happens if you type blind and hit enter

This sounds to me like the issue described in this thread:

A workaround when the screen is locked:
Switch to text mode with Ctrl+Alt+F1 and login as user, then kill the screenlocker with:

killall kscreenlocker_greet

Then switch back to KDE with Ctrl+Alt+F7 and you should be able to enter your password.

To prevent this do one of the following:

  • Enable “Require Password after:” in KDE’s screen locker/saver settings
  • Disable “Automatically Suspend after” in KDE’s power management settings
  • Disable “Lock screen after resume” in KDE’s power management settings (Advanced)

See this bug report for packages that should fix this: