If you uninstall MAC then this should remove its data stored in extensions storage.

You also possibly can check the storage for an extension via the about:debugging page.

• https://extensionworkshop.com/documentation/develop/debugging/

Thanks for your reply. I attempted (repeatedly) to just uninstall and reinstall MAC. But it won't budge. Every time I reinstall it, it just downloads a crap ton of containers. Could you provide more details about how to delete cloud storage from about:debugging?

I can see in Extension Storage a crap ton of entries, all tagged local. I tried to "Delete All". That resets the MAC addon, and if you click it it shows the welcome popup. After clicking sign in, it downloads again the crap ton of tabs. Is there a way to see the remote storage instead?

You can reset the password of the Sync account, that should reset all data on the Sync server. If that still doesn't work then remove the account and recreate it.

Yeah...Changing my password didn't work. As soon as I installed the add-on, it went to redownload all the thousands of containers. So the only solution in order to access my cloud storage...is to completely delete my account? I can't believe there isn't a better option.

Are there other devices connected to this account ?

Did you disconnect Sync when you reinstalled MAC?

You can try to disable syncing extension storage in MAC if that is possible or exclude syncing Add-ons via "Options/Preferences -> Sync".

Yes, there's multiple devices connected to this account. Only two of them are simultaneously online though. Should I remove all the offline ones too? Yeah, I unticked the Sync option on MAC before removing it. Then I changed the password. Then re-added it, using the new password. It still downloads the containers.

I'd very much like to keep sync working for the rest of the addons.

The fact that a single addon can mess the storage for everything else, while there's no direct way to access that cloud storage in order to fix it, keeps being a rather poor design option IMHO.

You can try the About Sync extension to check what data is stored on the Sync server via the about:sync page provided by this extension.

• About Sync https://addons.mozilla.org/firefox/addon/about-sync/

Close and restart Firefox to access the about:sync page added by this extension (see the about:about page for possible about pages).

There is an Engine Actions tab for each of the engines that allows to reset data. I'm not syncing add-ons, so I don't know if this allows to clear your data and upload it again.

Thanks! This seems indeed to pull the stuff from the sync servers. And I can indeed see where it goes all tits up. In extension-storage, the Object labeled as "1" is insanely big, taking thousands of lines, and I can see lots of references to the "tmp" named containers. I pretty much could safely delete that entry without fear of damaging much else.

However... I don't seem to be able to. The "Engine Actions" seems to refer to the Local storage, so the next sync will be like the first one. That doesn't help, I want to delete the Remote storage, just as its listed nicely here. I tried anyway just in case, to no effect.

OMG...I think this did it!

To erase Sync data, try this (turn Sync off first in the extensions preferences):

   Open extension console: Go to about:debugging#/runtime/this-firefox, select "Inspect" on Multi-account Containers, and select the console tab
   Type browser.storage.sync.clear();
   Manually sync through the browser (hamburger menu, your account, Sync Now)
   repeat step 2 and 3.
   To make sure it's working, you can type await browser.storage.sync.get();. It should return and empty object if it's working.

Seen here: https://github.com/mozilla/multi-account-containers/issues/1661

OMG...I think this might have fixed it!

To erase Sync data, try this (turn Sync off first in the extensions preferences):

   Open extension console: Go to about:debugging#/runtime/this-firefox, select "Inspect" on Multi-account Containers, and select the console tab
   Type browser.storage.sync.clear();
   Manually sync through the browser (hamburger menu, your account, Sync Now)
   repeat step 2 and 3.
   To make sure it's working, you can type await browser.storage.sync.get();. It should return and empty object if it's working.

Seen here:

https://github.com/mozilla/multi-account-containers/issues/1661

I'll keep testing a bit more.

Yeah...no. It seems to keep having issues and redownloading thousands of containers. Now whenever I run in the console: browser.storage.sync.clear(); and then sync manually, if I check with: await browser.storage.sync.get();

I still get a randon list of containers. It never returns empty. The containers IDs are different each time, but still...