After alt tabbing from underrail to say, pick a youtube video for background noise and tabbing back in you cannot target npcs or objects, the orange outline just plain not showing up. From my expierence so far the only way to fix it is to completely restart the game, its perfectly safe to save or do stuff in the UI/HUD besides attacking enemies because you cant target them.
To restate, I am using the most recent version of PROTON under POP! OS, i cannot verify if it is the same under different distros or under a specific older version of proton.
