Thats probably because the lockscreen is just a fullscreen application under X11, Weyland actually understands the concept of a lockscreen and keeps things a tad more secure.
I get the same problem on Fedora, its irritating.
I get the same problem on Fedora, its irritating.
And I hadn't that problem in KDE.
Invariably I miss the fact that the disk-activity light is still lit, start typing my password and then become annoyed because it only caught the last few characters. So then I have to wait AGAIN whilst it proudly announces an authentication failure and punishes me with a further delay.