Sync Edge Split Tabs

[DovieW]

Describe the feature you'd like to request

In Microsoft Edge (I'm on Version 121.0.2220.3 (Official build) dev (64-bit)), if I try to sync a split tab (there's a feature in Edge to split tabs and have 2 pages in one tab), Floccus will only sync the left tab.

Describe the solution you'd like

Both tabs should be recognized and be synced. They don't have to be in split mode when it's downloaded (but if it can be it would be nice, and remembering that some tabs are pinned would be nice too).

Describe alternatives you've considered

No alternative. I can't use split tabs together with Floccus sync tabs 🥲

[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 💙