Please allow an on-screen keyboard on login and lock screen to make KDE use possible on modern convertible laptops. Windows had this for about 14 years now. Sure someone must have noticed it's a good thing worth having in KDE, as well? I had several touch screen laptops/tablets, always put KDE on them, but just can't login without a keyboard.
The duplicate bug report is for the screen locker. Regarding the login screen, please report this issue to SDDM developers, if you are using the SDDM display manager. *** This bug has been marked as a duplicate of bug 181554 ***