[RMMZ] Error: No available storage method found (itch.io on Windows 10)

[Sarena]

I'm receiving the error message "Error: No available storage method found" when trying to play a Web browser version of my exported MZ project. It doesn't seem to happen on every computer, because I've gotten past the error message on one of my computers, so I'm not sure what's causing the issue.

I exported my game out of MZ using the Web browsers / Android / iOS Platform Deployment option, and when I go to play the game in a browser, I receive the error "Your browser does not allow to read local files."

So I uploaded my game to itch.io here.

Initially, I had received an error message that said "There was a problem loading your project: Too many files in zip 1433 > 1000) Please try deleting the ZIP file and uploading another." So I manually deleted some of the files I wasn't using (when trying the "Exclude unused files" option in RMMZ, it would just delete image files that plugins referenced/needed, so that wasn't an option for me to do). When I reuploaded it to itch with some files deleted, I was able to run it in my browser.

When I try to run the game in Chrome incognito window, I receive the error message in the topic of this post. And when my friend ran the game from her computer (not in incognito, but using Chrome as well), she also received that error. And on her other computer, she received the error "Failed to initialize graphics." instead.

The laptops we've tried are all Windows 10 and using Chrome.

Does anyone know why this might be happening and how I might be able to resolve this so that it works?

 

[Andar]

1) the original error (no local file access) is a security option of the browsers to prevent malware from websites to infect local files - and they can't always detect that it is a local website doing the access instead of a remote one.
There are several ways around this (including installing a local webserver) although I advice against removing the security setting in your browser because that would open you up to real external threats.

2) there is a very simple workaround to the problem of the engine not knowing files used by plugins:
make a map that is not connected to anything in your game, and then use the files in events on that map (show picture, play audio, as sprites, whatever).
It doesn't matter how you do that as the player will never enter that map, but the engine detect those files as "used" and you can now check "exclude unsused files".

3) the no storage error can be caused by two different things: the game has to store its data somewhere, and if your browser is set to incognito it also prevents all temporary saves to keep you incognito. Or it could be the problem of the no access rights on local space again...

 

[Sarena]

Thank you for your quick and detailed responses!

1) the original error (no local file access) is a security option of the browsers to prevent malware from websites to infect local files - and they can't always detect that it is a local website doing the access instead of a remote one.
There are several ways around this (including installing a local webserver) although I advice against removing the security setting in your browser because that would open you up to real external threats.

This makes a lot more sense now, thank you for clarifying this.

2) there is a very simple workaround to the problem of the engine not knowing files used by plugins:
make a map that is not connected to anything in your game, and then use the files in events on that map (show picture, play audio, as sprites, whatever).
It doesn't matter how you do that as the player will never enter that map, but the engine detect those files as "used" and you can now check "exclude unsused files".

This is a really great workaround, I'll definitely need to do that in the future!

3) the no storage error can be caused by two different things: the game has to store its data somewhere, and if your browser is set to incognito it also prevents all temporary saves to keep you incognito. Or it could be the problem of the no access rights on local space again...

It makes sense that the no storage error would happen in incognito mode after what you mentioned, thank you! Though one thing that's weird is that I have 2 different Chrome profiles. One of them works in an incognito window and the other doesn't, both on the same computer.

I am also still a little confused on why this is happening to my friend's Chrome browser that isn't in incognito though. She tried running my MV game here and it doesn't have the error/runs fine. So it seems to be something with MZ games specifically that isn't working. Maybe a new security measure that they implemented?

Here's the error message that we're getting when we open the console on the itch.io page:

Her non-incognito Chrome prints these same errors and warnings as my Chrome incognito, which also seems more and more like there's something in the browser that's blocking it for some reason.

 

[coyotecraft]

I believe the "No available storage method" error has to do with Chrome not liking the embeded Iframes. I can play non-embeded MZ games just fine in Chrome.

itch.io doesn't proved a non-embeded link. However you can find it by right clicking the game's frame > view page source > and search for a url containing "...index.html".
So you can have players follow a direct link to that, or ask them to use a different browser.

The difference between MV and MZ is that MZ uses localforage.min.js which is where this error message is coming from.
The explanation Chrome gives accompanying the error is this:

WebSQL in third-party contexts (i.e. cross-site iframes) is deprecated and will be removed in M97, around January 2022. Please use Web Storage or Indexed Database instead. See https://www.chromestatus.com/features/5684870116278272 for more details.