

Acceptable OOTB experience
KDE taskbar flicker sometimes on fullscreen mode. I "solved" it by change it's visibility to "Auto-Hide".
Game show "Oops, there is an error" message when i make a save (on DLC story), which cause corrupted save file
Permanent FPS drop if you frequently Alt-Tab

Game does not work on current default Proton version. The Custom Proton from GE solved the issues. Game is running very smooth
5.9-GE-5-ST GloriousEggroll
Custom Proton from Glorious Eggroll: https://github.com/GloriousEggroll/proton-ge-custom
There is slight crackling noises here and there. This also happened when I tried the game on windows, but a lot less than on linux
I was not able to start the game at all with normal Proton 5.0-9. But it worked with Proton-5.8-GE-2-MF.
I'm not sure if it's the update that fixed the video stuttering issues, but it's MUCH better than before
When video was laggy/choppy, the audio was also doing the same thing
Everything is choppy and laggy. CPU going crazy
I tested with custom Proton version, disabling ESYNC and PROTON_USE_WINED3D but none of these helped the lag issues :/