If you mistype your password then the lockscreen does react on pressing enter the second time (after reentering the password).
This is ONLY for the main enter button - NOT for the Num-pad enter button which continues to work.


STEPS TO REPRODUCE
1. Lock screen
2. Mistype password and press enter
3. enter new password and press enter again

OBSERVED RESULT
No reaction/submit from pressing enter button second time.

EXPECTED RESULT
Submit like first time enter was pressed.

The login can still be done by clicking with mouse or pressing the numpad enter button.

This regression appeared in Kwin 5.17, but I thought someone would quickly find and fix it ;-)