Your system information

• Steam client version (build number or date): 1733265492
• Distribution (e.g. Ubuntu): CachyOS
• Opted into Steam client beta?: No
• Have you checked for system updates?: Yes
• Steam Logs:
  steam-logs.tar.gz
• GPU: Nvidia RTX 4070

Please describe your issue in as much detail as possible:

This one is weird and extremely specific.
When playing in Big Picture Mode with a controller, and the game being played summons the on-screen keyboard to input text, the cursor for the on-screen keyboard is being controlled by some keyboard inputs. 'R' moves the cursor left, 'T' moves it down, and 'O' moves it up. Importantly, this is caused by both actual keyboard inputs, and on-screen keyboard inputs, meaning it is impossible to type many words. This issue has appeared in both Path of Exile 2, Warframe, and Shin Megami Tensei V: Vengeance. It occurs regardless of whether a game is running in Gamescope or not. It occurs in both Beta version 1735842154, and Stable version 1733265492. It does not occur when attempting to reproduce on my Steam Deck, and does not occur when summoning the keyboard manually via a guide button shortcut. This bug is also not reproducible on Windows.

Steps for reproducing this issue:

1. Install Steam through Pacman.
2. Install a game that summons the on-screen keyboard on its own.
3. Enter Big Picture Mode.
4. Start the installed game using a controller.
5. Bring up a textbox in the game that causes it to automatically summon the on-screen keyboard.
6. Attempt to type the R, T, or O keys.