Initially worked fine, but then started the next day and the containers had reset to the defaults in the multi-account containers button even through the add-on said that it sync'd all the containers in the side window.

Does not work as expected. I wanted to test synchronization between devices and it added all of the containers from one device to the other (so I had them duplicated). When I tried to delete them the duplicated ones were also synced.

I guess that the extension work fine as a backup of containers, but currently it does not really help with syncing between devices.

On a unrelated note, it does not respect the dark theme version.

Sorry, for the empty review before. I really did not notice that it had been posted without the text.