I don't have an answer, but I am interested. That said, apparently Firefox can now import and use Chrome extensions with the new update. I have yet to try it myself and assume your mileage will vary.
https://www.ghacks.net/2023/08/23/firefox-users-may-import-chrome-extensions-now/
The import requires the extension to also be available on Firefox
output from https://www.extensiontest.com/ doenst look like this specific addon could easily be ported or reproduced, mostly because the tabGroups API (ref. https://developer.chrome.com/docs/extensions/reference/tabGroups/) AFAIK is not available
ref.
... on the other hand i am not sure how required this "feature" would be just for the sidebar functions. i guess one could strip it out and check if the addon would still work "good enough".
edit: i briefly tried and failed, also because the addon is pretty obfuscated. So yeah the only ones who will be able to make it work is the addon developers i guess.
Have you tried running the extension on Firefox?
https://www.ghacks.net/2023/08/23/firefox-users-may-import-chrome-extensions-now/
This is just importing a list of extensions from chrome and matching them to a Firefox extension. If the extension doesn't have a Firefox version it won't fo anything.
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