Are there logs for when a proton-based launch fails?

[NetCrashST]

If I add some random game/app to steam, launch the exe with proton, but it just exits ; are there logs anywhere?

[Prezidentas]

not unless you force it to make a log

[NetCrashST]

Originally posted by Red Star Gopnik:

not unless you force it to make a log

and I do this how?

Can this be done from the gaming mode steam UI in any way?
or must I launch it in desktop mode via some cli ? (and what is the equiv?)

[Prezidentas]

it's a launch option for a game

PROTON_LOG=1 %command%

[NetCrashST]

Yep! found it , and for future readers, ref https://github.com/ValveSoftware/Proton/

[Marlock]

some extra hints for fixing Proton issues on linux PCs (many also apply to the Deck)
https://steamcommunity.com/app/221410/discussions/0/1636417404917541481/