This is a strange issue, but I tested it a couple times, and it happened both times: When downloading my big (~3.6GB) fully-released game that I just re-exported via Linux(CEF) instead of NW.js and re-uploaded, a problem is that the Steam Deck completely freezes right at the time that the pop-up says the game finished downloading from Steam. Very odd. I wait a bit, then hold power down to force shut down, turn it back on, and run my game. It crashes at startup, so I say in game settings to verify files, and it says it found ~350 files it will reacquire. It does so, and then the game works! Which is awesome!

So the last challenge is: Is there a way I can prevent the Steam Deck console freeze at the end of the game download? Assuming this will happen to everyone's Decks, they'll all have to repeat the steps I did, which will inconvenience them, and I'll feel I have no choice but to include the steps in a troubleshooting area at the end of the game store description, which seems unprofessional and may hurt sales. Note that I first uninstalled the game, before downloading it fresh, but the freeze still happens at the end. I assume this isn't just an issue with my particular Steam Deck, since it never happened with any other game download. Thanks

(Also a side-question: Can I safely also use the Windows and Mac exporters in C3 to replace the previous NW.js builds of my game, and be sure that they'll work? Since I have no way of testing at least the Mac build, and my game is already out on Steam, so I don't think Steam support would test my game on other systems like I assume they did when I first put it up. I read in these two pages...

construct.net/en/tutorials/exporting-windows-webview2-2685

construct.net/en/tutorials/exporting-macos-wkwebview-2718

...things about signatures or something to run games on Windows and especially Mac, but those pages didn't specify if all that effort also applies to Steam games. I didn't do any of that stuff before with NW.js, and Steam support never told me my game didn't run on Win or Mac, and I only tested it on Steam Deck myself.)

I only have experience with the NW.js export option, but I want to expand to the latest and greatest Linux exporter, even if only for the Lin64 build of my game, because one of my games is big, 4GB, so it often results in a gray "NW.JS" screen on Steam Deck, requiring me to restart the console and run the game again to usually fix it, which I'm sure results in a higher customer refund count, so I figure getting rid of NW.js gets rid of the NW.js screen, so I want to use the Linux(CEF) exporter instead.

There might be an up-to-date guide I'm unaware of for this. What are currently the best steps for this? I only need Achievements to work, I don't do anything with things like leaderboards or DLC. I have all my Achievements input using the 'Greenworks' plugin v1.0.60.0, but it even says that's for 'Accessing the Steamworks API from NW.js', so I'm guessing I need to search for and duplicate all Achievements in my project to also be triggered thru the latest 'Steamworks' plugin. But first I need to figure out how to not just get a black screen on Steam Deck.

What else do I need to know or do to not just give me a black screen on Screen Deck? I read these two pages:

construct.net/en/tutorials/exporting-linux-steam-deck-3155

construct.net/en/make-games/addons/1105/steamworks/documentation

Are there any steps missing? (Note I don't know what to set the Project ID to in C3 so I just give it whatever looks nice, like "com.company.game".) I set the Linux export to x64 and 'startup full screen'. I extract the resulting zip's x64 folder. I don't make any changes or additions to the contents, other than just one try with the steam_appid.txt containing the app ID being included in the x64 root folder. (unlike back with NW.js in which I added greenworks nodes as well as files called libsteam_api.so and libsdkencryptedappticket.so to the root folder, lib folder, and package zip.) I upload the x64 path to Steam the usual way (I use the SteamPipe Build Uploader), publish, download on Steam Deck, hit play, get a black screen. Note I'm trying this with a smaller 1GB game that's not fully out yet, not yet my big 4GB one.

What step am I missing? Thanks

UPDATE: I did it! Unexpectedly, the problem was just the "Greengrinds" addon. Despite its popularity on the addons page, it results in a black screen upon loading the game! Deleting it from my project allowed my game to run on Steam Deck. In case this is a variable regarding the Greengrinds plugin, I also have these addons in my project: Greenworks, Steamworks, SteamworksPlus. So it's possible that Greengrinds only causes a black screen at startup when one of those are included as well. I removed Greengrinds from my addon manager so this never happens again. Thanks! I'm going to test Achievements next, thru the Steamworks addon.

UPDATE 2: Attempting to unlock an existing Achievement thru the Steamworks addon on Steam Deck crashes the game? Is this a known issue or am I doing something wrong? UPDATE: It worked when I tried again! Although all I did was change the Achievement test to being if I hit Y instead of just at the start of the layout, and as a result had to do another export process again, so unsure what caused the crash before or what fixed it in this attempt. Now, so far so good with exporting via Linux(CEF) and Achievements via Steamworks addon. Next will eventually be to try it all on my 4GB game and hope no issues. Though I notice this results in a new game save, but better to do while the game is younger.

Webm format should work on Steam Deck - we have an intro video playing in our game on startup, no user interaction required.

You don't need both webm and mp4 files, just keep the webm one.

Hmm it still doesn't work for me. I'll try my backup plan of converting the videos to gifs/animated sprites and running the audio alongside.

UPDATE: Thankfully, I got the video-playing working on Steam Deck after all. What seems to have happened is that because C3 didn't tell me whether or not the filenames typed in the events needed to have the ".webm" extensions included or not, I went with duplicates of the play events, repeating the play event one with and one without the file extensions, assuming the right one would stick. It seems this worked in preview, but not on Steam Deck, if that makes sense that that would happen. So I only kept the events that included the extensions and it now works.

I do have a small suggestion from this though: that C3 simply include the fact that you need to include the extension for videos (stated in C3 itself, not just in the manual). That would've likely helped me avoid this complication. Thanks!

The "main.js:29 [Project] Exception opening: Error: cannot find object type named '[object name]'" error is so constant that I want to understand it once and for all.

(I could be wrong, but I suspect online backup solutions are to blame for this, such as pCloud and Icedrive, despite that they're supposed to help, not hinder, because they so often create "(conflicted)" (pCloud) or "[conflicted]" (Icedrive) versions of Construct 3 files. Why do they need to do this, when my local files are garanteed to always be the ones I want, not some outdated online backup's? And then I'm working on a project or event sheet that isn't even the latest one, and I don't realize it til later, and need to consolidate the two. I hate online backup services, but I can't risk not using them either.)

What's the fastest and easiest way to fix "Cannot find object type named [object name]" errors? I see the object exists in both my project.c3proj file, and in the objects folder where it belongs, and that the name is the same in both. Why can it claim to not find the object, when it's clearly there in the right objects folder? Because of online backup services, there are two versions of the project.c3proj file, but I assume C3 uses the one that doesn't say "[conflicted]", which is the one that I confirmed has the object name in it.

EDIT: For anyone else who gets this error, one thing I did just now, that at least opened the project (but I'm unsure about if I'm missing anything--everything looks okay so far, as being my most recent work), is that in my C3 project folder, I made a folder called "(conflicted file backups)" and simply dragged in the versions of the files that Icedrive created "[conflicted]" versions of, in this case these 3...

objecttypes.uistate [conflicted]

project [conflicted]

project.uistate [conflicted]

...just in case I ever need them again, and then opening the project worked. Which suggests, as strange as this seems to me, that C3 was actually opening the project based on the files named [conflicted] instead of the ones not named that! If such a thing is possible? But all I know is, when I separated the files with [conflicted] in their names, it opened, and, at least from what I can see, seems all well.

The latest Greenworks addon for C3 I use is 0.60.0 because I read in C3/Steam export guides that NW.js version 0.60.0 is the latest one that works well in testing on Steam, instead of failing to load or Achievements not working, but I notice that Greenworks 0.60.0 doesn't feature an action to determine the completion percentage/value of an Achievement, for Achievements that I want to show progress for, it only lets us 'Activate achievement' 100%.

I hope there's a way to do Achievement completion percentages/values, such as by using a later version of Greenworks, for a later NW.js version that will still work, or even by using the Steamworks addon instead of the Greenworks one? (assuming it's not just for Windows, as I need to output to Linux and Mac as well)

Has someone successfully done Steam Achievement completion percentages/values, and, if so, what version of Greenworks/NW.js do you use/recommend? Thank you