With the huge SteamOS 3.8 update now out, a few hiccups were expected - but thankfully, they’ve already patched one of the major annoyances.
Burning a bit of the midnight oil so to speak, Valve released a stable SteamOS update on Saturday, June 20th to solve the Desktop Mode getting stuck on the lock screen unless you could hook up a physical keyboard. The on-screen KDE Plasma keyboard didn't work, nor did Valve's own on-screen keyboard. Bit of a woops.
From the changelog:
SteamOS 3.8.11 has just been released for all users with the following changes
General
Fixed the virtual keyboard being inaccessible on the Desktop Mode lockscreen
Testing it with the update today and it is indeed properly fixed so the KDE Plasma on-screen keyboard will come up properly and input works. Nice.

Pictured - Steam Deck OLED - KDE Plasma lock screen with on-screen keyboard working



