Integration with other extensions - Obtain tab metadata

[unode]

Describe the feature you'd like to request

I would like to add support for two other extensions that I currently use Multi-Account Containers and Tree Style Tabs.
To begin with, in order to support integrating with these, one would need to be able to store tab metadata. Namely:

• The container ID from Multi-Account Containers - this is typically a numeric index
• Tree Style Tab position or parent-child info - I'm not yet sure how this is stored but could be extracted as one UUID. Each tab would have a parent that could be another tab or blank. Blank would imply that the tab is displayed at the first-level or root.
• Window ID - Instead of restoring all tabs on a single Firefox Window, it would be convenient to restore them in different windows.

Describe the solution you'd like

First I would like to know if it is possible at all to obtain and store this type of metadata.

Describe alternatives you've considered

At the moment I'm reopening (in the right container) and sorting/reorganizing tabs manually after they are restored by floccus. It's quite inefficient and time consuming though.

[github-actions]

Hello 👋

Thank you for taking the time to open this issue with floccus. I know it's frustrating when software
causes problems. You have made the right choice to come here and open an issue to make sure your problem gets looked at
and if possible solved.
I'm Marcel and I created floccus and have been maintaining it ever since.
I currently work for Nextcloud which leaves me with less time for side projects like this one
than I used to have.
I still try to answer all issues and if possible fix all bugs here, but it sometimes takes a while until I get to it.
Until then, please be patient.
Note also that GitHub is a place where people meet to make software better together. Nobody here is under any obligation
to help you, solve your problems or deliver on any expectations or demands you may have, but if enough people come together we can
collaborate to make this software better. For everyone.
Thus, if you can, you could also have a look at other issues to see whether you can help other people with your knowledge
and experience. If you have coding experience it would also be awesome if you could step up to dive into the code and
try to fix the odd bug yourself. Everyone will be thankful for extra helping hands!
One last word: If you feel, at any point, like you need to vent, this is not the place for it; you can go to the forum,
to twitter or somewhere else. But this is a technical issue tracker, so please make sure to
focus on the tech and keep your opinions to yourself.

I look forward to working with you on this issue
Cheers 💙

[marcelklehr]

Hi @unode
This is non-trivial as we try to support multiple browsers and the API for additional tab features is largely non-standardized, I'm guessing for TreeStyle Tabs it's even not available at all. I haven't researched this, yet, though