

I have played this on both Windows and Linux, and I don't really see a difference.

Fullscreen seems to trigger performace issues
Game sometimes drastically reduces performace and FPS depending on action

No issues, great performance -- a must-play on Linux
Outer Wilds runs flawlessly out of the box with Proton Experimental. No tweaks were needed. Performance is smooth, loading times are reasonable, and I encountered no crashes or visual glitches during my playthrough. Controller support (tested with Xbox controller) works perfectly as well.
Highly recommend for anyone curious about this unique space exploration game — one of the best gaming experiences I've had on Linux.

Can install the game, but can't run it. I tried the various tinkering methods in this thread, but I can't seem to get it to open
Computer automatically goes to sleep while I'm playing with a controller

Works great
Game freezes on each loop start, I have to get out of and again in fullscreen each time. Still playable though.
Appart from the fullscreen issue it runs flawlessly
It works.
Works out of the box
No issues playing it.

Runs out of the box with added stability when compared to Windows.
Enjoy

Works perfectly. Even on wayland
I previously had problems running it on Wayland in Arch Linux. And on X11 in Arch Linux, it had issues with the KDE Plasma task bar showing breifly when dying. After switching to Fedora the issues disappeared and works well in Wayland

Works Out Of The Box
Sometimes the game wouldn't detect my PS4 Controller in the main menu. This was usually fixed by changing the controller type in the settings back and forth.
Runs perfectly

To achieve a stable 60fps, you must at least bring the resolution from the Properties menu down to 1024 x 600.
Use FSR in the Steam Deck's (...) menu as well in order to achieve viisual clarity to closely match how it originally looks while still having roughly 60fps. Nobody seems to acknowledge this as an option for better performance.
everything is working properly

Works well but has lag sometimes
When using an Xbox Controller, the focus button when floating in space just becomes unresponsive. This is fixed by using the mouse to focus and then going back to the controller. The focus button works afterwards.
Game generally runs at 40-55 FPS. If I die and wake back up, FPS drops to ~20FPs or in some cases ~10FPS. Exiting to the menu and then "Resuming Expedition" fixes the issue. This always happens.
In some instances, when in the ship, using the landing camera for some reason drops the framerate to ~7FPS. Goes back to normal when going back to cockpit view.

Set refresh rate to 47 Hz

Go experience it for yourself.
There's some very rare fps drops on one place, but that may not necessarily be a proton problem
Tinkering Steps: had to reinstall on a non ntfs drive. I used the home drive which was formatted in btrfs after consulting this guide, after that worked perfectly on default proton

Tried different proton versions
alt-tab freezes the game in fullscreen
PS5 controller not working without steam mapping
Game completely freezing every few minutes

Occasional audio lag, but hardly noticable when playing
Using this to correct my initial entry that said it didn't work. I had it installed in a drive that was formatted with the wrong format
gamemoderun %command%
Jeu sympatique et parfaitement adapté à Linux.

Pretty good experience out of the box.
Launching in fullscreen freezes all other apps in the background but the game itself works.
Runs at around 50~ FPS with medium/low settings and some customizations.

Using Steam Input causes some of the button prompts to be incorrect, but the game runs fine otherwise.
Noticed doubled button prompts in ship log at one point.
Could not get game to detect DualShock 4 without Steam Input. The same controller works on Windows.
Works perfectly out of the box

Works great out of the box

Black screen after selecting "New expedition"
I am able to install and run the launcher (both with big picture and normal mode) but when I press on New Expedition the laptop is completely stuck with black screen. Even the key combinations don't work but with big picture mode I am able to hear the Steam menu after pressing the XBox controller main button.

My installation was not working at the beginning, so I just launched Steam from a terminal and saw the output. Looks like that if you install the game in a NTFS drive, the game fails to launch if the drive is not mounted by your own user. Followed this guide and got it running smoothly.
If you are not in an NTFS drive, everything should be great!

Not running, probably missing a dependency
Tried on Debian 12 as well. Tried running through every Proton version 6.3-8 and up.
Works out of the box!

Set graphics settings to low to save battery life
Occasionally after resuming from sleep there would be minor audio crackling. Restarting the game fixed it.

Disable the "Force Composition Pipeline" in Nvidia settings.
Fullscreen was not working with Nvidia's "Force Composition Pipeline"
There is a need to disable the "Force Composition Pipeline" in Nvidia's settings. Without that the game is stuck on fullscreen, freezes the system and can't be played.