Hello,

Since the game doesn't exist on the Steam servers, so there is nowhere to upload and store screenshots for it. This is unlikely to change as it would mean running a free image hosting service.

I figured it was something like that but on the other hand it's perfectly possible to upload screenshots of the Deck UI to Steam which isn't tied to any game at all. I would have expected screenshots of non-Steam games to be considered as non game screenshots as well.

You're right. Screenshots are tied to your Steam account, so maybe it'd make sense if it could take screenshot uploads from non-steam games. The origin shouldn't really matter.

Maybe a Option to Upload these kind of Screenshots somewhere else like imgur?

you can put them in your "artwork" section of your profile

generally if you dont own a game in your library you cant upload screenshots or videos to that appid

I've uploaded screenshots of non-Steam games to Steam without issue on the desktop client, so I think this should be possible.

Not really sure why there are people stating the issue is non-Steam games. It’s not. I have screenshots from the early 10s of World of Warcraft and more. This is a valid issue.

This would be nice to have fixed considering a large portion of people who use SteamOS are SteamDeck users that are emulating games which are going to be non-steam.

And as was stated previously. Uploading non-steam games works everywhere except in the actual Deck Game UI mode.

The reason for this is that the appID for nonsteam games is being truncated when a screenshot is saved. It's supposed to be a 32 bit unsigned integer but for some reason the last few bits get stripped before the screenshot is saved. Because of this Steam has no way of knowing which app the screenshots belong to. This is why they don't show up under the "your stuff" section, and why you can't upload them (the Steam client tries to match the folder of the screenshot with an appid and cannot do so).

Source: I'm the author of the Shotty plugin and had to navigate this mess to get the correct app names when aggregating screenshots.

At a bare minimum, it should store all screenshots in a less obscure picture folder like ~/Pictures or something like that, right now we need to switch to desktop mode, navigate to /home/deck/.local/share/Steam/userdata, search for any screenshots folders, go through all of those until finding the one you need, which is painful.

This still isn't resolved. Imagine getting a new steam deck and wanting to show screenshots to your friends to show how great the device is.. but you can't upload screenshots... it's a basic feature and my friends just laughed at me over it. Yes, the steam deck got laughed at by my discord group for not being able to upload screenshots.... its a basic feature from a decade or more ago, yet the steamdeck cant do it.

Just confirming this still randomly happens, it just refuses to upload screenshots to Steam at times.

"An error occurred while uploading this content"

Is there any way we can get more details to track down what causes it?

Just confirming this still randomly happens, it just refuses to upload screenshots to Steam at times.

"An error occurred while uploading this content"

Is there any way we can get more details to track down what causes it?

Its very easily to build I can cook up a plugin in like 10 minutes (non steam games screenshot uploader). I upload my NSG screenshots all time time.

The error still persists.
Almost four years have passed since the device's release, and screenshots from the Steam Deck still have to be transferred via a flash drive...

The issue is there apparently merely because the directory name (as well as the gameid in screenshots.vdf) gets calculated incorrectly when saving the screenshot.

When you add a non-Steam game via the desktop mode, and then take a screenshot of it in the gaming mode, Steam properly writes the correct, very large app ID to the shortcutnames subkey of screenshots.vdf. However, when you actually take a screenshot, the directory with it and the appid receive a much smaller value, and apparently when you try to upload a screenshot, Steam assumes that you're uploading it for an actual Steam game under that small ID, rather than for a non-Steam game.

More precisely, the correct app ID for a shortcut to the PCSX2 Flatpak named PCSX2 on my Steam Deck is 14143842444139036672, which is C44905C402000000 in hexadecimal. But screenshots actually end up in the 4785604 directory instead, that is 4905C4 in hexadecimal.

Similarly, for Visual Studio Code, the app ID should be 12801827758715961344, or B1A93A8502000000 in hexadecimal. Screenshots, however, get saved to the 11090565 directory, or A93A85.

So, it looks like Steam merely takes the lower 24 bits of what should be the hash of the application name (and maybe some other shortcut parameters, though maybe not given the additional observation about the same app on different platforms below) as the directory name, rather than placing the full 32 bits (or possibly 31 bits, and always 1 above) in the upper half of the 64-bit app ID, with the lower half being 02000000, and using it instead.

What sounds most likely is that in the name calculation, Steam passes the shortcut ID to some wrong full app ID constructor that expects a Steam app ID instead, or something like that, so it places it into the wrong structure field and with the incorrect app type value (0, store app, rather than 2, shortcut).

If you create a directory with the full shortcut app ID from shortcutnames at the end of screenshots.vdf as the name, and copy your screenshot there, after you restart Steam and maybe look at the game in the library, Steam (this works fine in the gaming mode too) will automatically create a thumbnail and properly register the screenshot in screenshots.vdf, and you'll be able to upload it in the gaming mode just fine. It will also be displayed in the Media section in "Your Stuff" in the library entry. And moreover, if you have also played the non-Steam game with the same name elsewhere, including under a different path, and uploaded screenshots of it there, your new screenshots will be grouped with them in the Steam Community — I have both Windows and Steam Deck screenshots of PCSX2 in the same place on my profile.

Screenshots of mods (like Valve game mods installed to SteamApps/SourceMods or the Half-Life 1 directory) may also be an interesting thing to recheck, because they have their own app type value (1) and app ID calculation (with both the base game app ID in the lower 24 bits and mod directory hash OR 80000000 in the upper 32 bits, like 10210309621176860892 as decimal or 8DB24E81010000DC as hexadecimal for Research and Development with SteamAppId 220, where 8DB24E81 is CRC-32b of Research and Development, 0DB24E81, OR 80000000).