I could never understand why they were not synced. Its so incredibly frustrating, and the official reason does not help.

I simply don't understand Mozilla anymore. The power users are also the unpaid evangelists/marketers. They seem determined to alienate this demographic while iOS'ifying Firefox for a general audience. Which is great and all until they realize they don't have a marketing budget to complete with Google and MSFT.

> I think it was issue 339 on GitHub. They basically explain they won't add it to sync data because there is no containers on mobile.

Makes you wonder how on earth their data sync is working with regards to mobile. Surely if it doesn't have the components to leverage the data it just wouldn't read it..?

Its possible to implement the concern was that people would leak their cookies into the default container.

They should be essentially syncing but not syncing any non default container data into mobile.

Basically they had some work to do on the server end I think.

I too lost my multi-containers and assignments. I was just reading this (2017) discussion: https://github.com/mozilla/multi-account-containers/issues/3... and noticed mention of file 'containers.json', which I found in my current Firefox profile. It contains the descriptions of the containers I created since yesterday (for the 3rd time).

So it looks as though a manual backup of that (or the whole profile, knowing its in there) at least will end that chore.

But you still lose the Container -> websites associations. The same page recommends: "An effective way of exporting and importing containers safely is using ffcontainers."

The page for that syncer is here: https://github.com/pierlauro/ffcontainers ... but it's on hiatus at this moment.

containers.json wasn't enough in my experience. Still went through some kind of reset due to the way the plugin initializes.

ffcontainers looks promising but couldn't get it to work (spaces in my path..) probably needs a bit of a clean up.