Bug description: As soon as you click on the account icon in the main menu, the game crashes.
Bug reproduction:
1Step.Open Game
2Step.Click on the account icon
Environment: Steam deck, steam os v 3.5, game version 1.7.1276.
Attachments: I have a video, but the forum does not allow me to add videos to attachments.
Hey there!
So unfortunately, with it being a Steam Deck, not all games may be fully supported. ( This is due to it being on a completely different Operating System / OS. )
Our fully supported OS at this time are Android, iOS, and Windows.
Steam Decks operate using their own called SteamOS.
This might be a result of why you may be crashing.
More information can be found here:
It goes over some fixes and suggestions that may be of help. 
[ NOTE ] - This is something that I can bring to the team and collect a more concrete answer for you on, though.