
slight crackling
mouse input laggy and feels simillar to having mouse acceleration on, not noticable with high fps
using default steam launcher the game does not launch, using umu though the game is completely playable from start to finish, only issue is some audio crackling and slightly broken mouse input, but you might have better luck than me running the game. i tried chapter 4 but i think that previous chapters would work too.

On Desktop with AMD GPU videos do not play. Steam Deck and desktop nvidia works fine

Runs out of the box
With nVidia videos do play, with AMD (except Steam Deck) they don't
Videos do not play on AMD (except Steam Deck)

--proton
Chapter's one three and four work perfectly out of the box no tinkering needed that is to say i havent played chapter 2 on linux yet.

gamemoderun %command%
When fullscreened, Alt+Tabbing results in the game still being in front of everything and you have to manually click on a different program on your taskbar for it to come in front of the game.
Depending on the area you are in in Chapter 4, performance heavily degrades, probably because of the models of the monsters. In an area purely based on Puzzle solving without the inclusion of Yarnaby and such, even on High I can get stable 165 FPS, yet when it's a scene with Yarnaby or especially Doughey, even on the lowest quality possible (everything turned down to minimum) it tanks my FPS down to 10 FPS.
I do hope it's just a problem with the game itself, or maybe a newer/different Proton version would do the trick, but currently I find it hard to play the game when every cutscene or area with the main monsters of Chapter 4 tanks my game so hard that even Powerrpoint has better FPS.

[chapter 4 aka dlc3] The game softlocks at the part where "doctor" laughs at you (around the start of the game, first cutscene where you can't move camera). Also steam overlay doesn't open when in this softlock and cursor inside the steam window disappears and doesn't function (though arrow keys for moving in library work)

Crunch button

Fulscreen videos are missing with Proton Experimental. In Chapter 1, this includes the main title screen (instead showing a no signal image which makes the white text illegible) and credits. This doesn't affect gameplay. It works perfectly with GE-Proton
With Xwayland + openbox, full-screen is borked. Launching in Sway allowed me to switch back to borderless mode, which was the default value. Works out of the box.
Seems to run flawlessly with GE-Proton.
Works like a charm

MANGOHUD=1 MANGOHUD_CONFIG=fps_limit=60 %command%
Renamed intro video files (.mp4) to skip intros
Didn't test default Proton

In Poppy Playtime chapter 3, the first load and videos are broken with Proton Experimental.
With GE-Proton9-1 it works perfectly.

Creepy fun!
Game worked great out of the box. Booted up a bit slow the first time we played it but worked fine without problems. No tinkering needed.
Chapter 3 crashed ONCE. Since then everything works perfectly.

When trying to luanch the game I get a fetal error
It is possible that the devolper didn't allow older GPUs to run this game, there is no proof of this, it is my best hypothisis for why this game works for some and not others.

i don't know about the other comments in here but the chapter 1 runs perfect from start to finish, didn't try the other chapters

-dx11
I noticed a few small graphical bugs, mostly involving reflective glass surfaces.
it crashed on launch once
I did panic at one part thinking my save had somehow broken, when several doors I had unlocked were locked again when I loaded my save, and an item I was literally holding could be picked up again. However, it was a false alarm, it did not hinder my progress in any way, and I was able to continue the game just fine. I assume this was a bug with the game itself and not proton anyway.
Game ran basically perfect once I installed the custom proton ge version.

gamemoderun DXVK_ASYNC=1 STEAM_COMPAT_DATA_PATH={location}/.steam/steam/steamapps/compatdata/1721470 STEAM_COMPAT_CLIENT_INSTALL_PATH={location}/.local/share/Steam {location}/.steam/steam/steamapps/common/Proton\ 7.0/proton run {location}/.steam/steam/steamapps/common/Poppy\ Playtime/WindowsNoEditor/Poppy_Playtime.exe -dx11
Videos don't work
My son was pestering to make the game work after the last update so I tried various combination of things. Launching it from the command line in the manner above makes it perfectly playable, but the main menu and videos are borked.
The command line could maybe be simplified (I'm not sure which of the magic incantations are really required), but I didn't have time for that.

gamemoderun DXVK_ASYNC=1 %command% -dx11
Slight crackling in the audio, simply restarting Pipewire after launching the game solved it however.
- (Chapter 1) Some VHS tapes would simply have their videos freeze, even while audio kept going.
- (Chapter 2) Furs like on Huggy Wuggy and Kissy Missy appear slightly distorted and weirdly shaded. This isn't related to the shadows issues mentioned also in this report, as setting it back to Best didn't fix it.
(Chapter 2) The "Shadows" setting needs to be set to Low for certain areas. Normally at average, I get roughly 150-200 FPS at max graphics. However, in certain areas like the Game Station, I get hard capped to 30 without setting Shadows to it's absolute lowest setting.
- (Chapter 2) Some physics objects were very active and would ping across the room when pushed. This is minor however.
- (Chapter 2) I'm not sure if this is related to Proton, however I can't find any other documentation on this bug so I'm putting it under Proton. In Chapter 2 Statues, if you happen to be midair or mid-grapple when the lights go on, PJ starts moving at light speed. He's meant to adjust to your speed, so this seems to be a case of him losing track of you and the game just falling back to the fastest speed. Either way, it made the minigame near impossible.
Most issues seem to be in Chapter 2. I experimented a bit to try and mitigate these with launch options as best as I could, but simply can't find any way to make most of these better. I hope Chapter 3 is a bit better supported, as I do genuinely enjoy this series. I don't want to have to be stuck with Windows for a game that, realistically, should be running in Linux perfectly fine.

I am not sure but I think I had to change the resolution settings, however thats not unusal since I got a 4K Monitor and most Games are optimized for 1080p so I had to change that but otherwise there where zero problems.
El juego solo se ejecuta en el menu de inicio , que version de proton recomiendan que use

Wszystko działa poprawnie jednak należy wskazać ścieżkę do folderu z plikiem exe i dodać go jako gra spoza steam z uwagi na PlaytimeLauncher
-dx11
Trzeba trochę pomajstrować ale jak się chce to się da!
gamemoderun %command%
I recommend using BigLinux with performance mode on
The game works fine, but videos did not play.
Controller worked, but certain action not supported.
Le son de le cinématique d'introduction est parfois décalé
Quelque lag juste après avoir démarré, sinon rien
I add a second "run" also on button L1 (the default on L3 hurts my finger on the very long run in the final fase)
Better reducing a lot the stick sensitivity (easy to do in game settings)
I had a bug but I think is the game and not the Deck: in the last puzzle (just before the big scare jump...) placing the toy didn't work and I had to restart the autosave (and doing all the section from begin.... there are no custom saves)
Crashes at loading with Proton-6.21-GE-2 (UE4 LowLevelFatalError). Crashes at startup on Proton-6.20-GE-1.
Doesn't work.
At the beggining the video and the audio were out of sync
For it to run on my hardware, it did required the fsr fullscreen hack, but this says more about my hardware than the game.
The colored bar screens never transitioned to the game. Manually loading the last save fixed it, even at the very beginning.
I could not see or hear VHS tape video
Had to switch to experimental and was missing video & audio on VHS tapes, but otherwise the game worked great. Noticed a very small amount of stuttering when it was auto-saving, but not enough that it effected gameplay.
no issues here, hell even the VHS tapes work
Game will not load on newer versions of proton only on Proton-6.21-GE-2 If you are having problems with the game not loading then lower graphical settings at the main menu then load the game then change it back to your desired settings.
Didn't Launch For Me
Played the first 5 min without issues
All game work fine with GE-Proton7-17, but WASD control does not works, so it's impossible to play.
All keyboard works fine, but WASD doesn't works
Video intro lagging behind sound
The game performance is comletely borked, some of these puzzels like Music memory require a fast pace with stable fps.
Swapped triggers to correspond with the hands in game. Changed the X button to E to interact and the B button to CTRL to crouch
Some loading logo's get cut off.
Game for the most part becomes borderline unplayable with fps dropping as low as single digits.
Video's play fine on latest build on the deck, but performance is so bad and inconsistent that it become unplayable. With mangohud it shows that the game is primarily bottlenecked due to GPU. So some custom configs with super low settings could fix this. But out of the box it is not playable.
Only game menu and intro scene showing
The game starts normaly and lag a little after that the game freeze or crash

This works PEFECTLY with Proton 6.21-GE-2