Since the update to Manjaro Stable of 28.04.2021, the order of the character-mode virtual consoles and of the virtual console where KDE Plasma is running is off by 1. /dev/tty1 is now uninitialized ─ it doesn’t even show a login prompt ─ and Plasma is now running at /dev/tty2, as you can see below.
It seems the same issue is present in testing and unstable, so, apparently was not obvious to anybody else (including me) before this mention of it from you.