Mafia broken since proton-5.13-6 and above

[stsp]

Compatibility Report

• Name of the game with compatibility issues:
  Mafia (Lost Heaven)

• Steam AppID of the game:
  40990

System Information

• GPU:
  [AMD/ATI] RS780L [Radeon 3000]

• Video driver version:
  mesa-24.0.5

• Kernel version:
  6.9.0-rc4

• Link to full system information report as Gist:
  I don't think it is relevant.

• Proton version:
  5.0-10 is the last version where the game works fine.
  5.13-6 is the first broken version.

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.

I don't think the logs are relevant.

Symptoms

Symptoms depends on a proton version in use.
On latest proton-experimental, the problem is
that the keyboard controls have something like
30 seconds lag, so the game is uncontrolable.
But that depends on a situation, eg in menus
the controls are good. But in the game itself,
the character reacts to a key-press something
like 30 seconds later.

Reproduction

Run the game and start playing. Try to control
the character or drive the car - you can't.

[kisak-valve]

Hello @stsp, we're using one issue report per unofficially supported game title, so I've gone ahead and transferred this issue report to #2812 (comment).

[stsp]

But please note that its a regression.
Shouldn't the regressions be handled
on a fast-track?