A Fishermans Tale (559330)

Compatibility Report

• Name of the game with compatibility issues: A Fishermans Tale
• Steam AppID of the game: 559330

System Information

• GPU: NVIDIA GeForce RTX 2080
• Driver/LLVM version: nvidia-440.82-12
• Kernel version: 5.6.11-arch1-1
• Proton version: 5.0-7

I confirm:

• [*] that I haven't found an existing compatibility report for this game.
• [*] that I have checked whether there are updates for my system available.

Symptoms

The game starts fine but the knuckles device mapping isn't loaded.
The game is therefore unplayable as you can't do anything in the main menu
motion of the knuckles is recognized, the buttons are not.
upstream once had the same problem on windows, but fixed it:
https://steamcommunity.com/app/559330/discussions/2/2673381715696034134/?insideModal=1#c2673383081706506601

this seems to be exactly the same bug as in
https://github.com/ValveSoftware/Proton/issues/3483
the only difference is, that you can workaround the issue in Walking Dead as there is a community controller setting available.

Start by reviewing the linked Proton issue #3483 and the upstream Steam discussion, then reproduce the report with A Fisherman's Tale, Proton 5.0-7, and a Knuckles controller. Done means the game's Knuckles device mapping loads and its buttons work in the main menu.