https://github.com/sissbruecker/linkding
Linkding has plugins for Librewolf (privacy aware Firefox) and all the Chrome-garpage (Brave, Vivaldi, etc.) that can handle tagging as well as inject your own bookmarks into your search results.
I'm using linkding at the moment https://github.com/sissbruecker/linkding which also has a browser addon, the only missing thing is some form central user auth but we're using it as it is.
Linkding: https://github.com/sissbruecker/linkding
[1] https://github.com/sissbruecker/linkding [2] https://apps.apple.com/nz/app/linkthing/id1666031776
It's slightly better than the browser bookmark manager.
While I'm not close done curating (the dead/expired/out-of-date links)... I needed to collect it all in one central place, and [linkding](https://github.com/sissbruecker/linkding) is fitting the bill quite nicely. I'm using the tags and description field to annonate and sort the mess of bookmarks. It has a simple to use rest API, uses SQLite, and you can import/export bookmarks using the Netscape bookmarks html format. Best of all, it's OSS you can self-host on a RaspberryPi or even for free on say fly.io.
After a few years of using it I signed up for an archival account (which costs extra $39 per year). My credit card was charged, but I wasn't able to archive any page; the option to do so was never there. I emailed support (I guess it goes directly to Maciej) and NEVER got an answer, despite being a paid customer and following up several times. I ended up having to do a charge-back on my credit card. Very unprofessional.
On the flip side, that made me look into self hosting and now I happily run a linkding [1] instance on my NAS. I never really cared about the social aspect of it.