There are so many out there, a few that I came across include:
- Wallabag ( GitHub, Website): Older, long history, somewhat clunky now?
 - LinkWarden (Website): Focus on multi user and teams?
 - Raindrop.io (Website)
 - Omnivore (Website)
 - Hoarder (GitHub)
 - Shiori (Article)
 - Readeck (Website)
 
Having a giant comparison table for this might be nice


I wish they would finally finish that rewrite in Rust so that it can be properly self-hosted again. The old Python2.7 version is a security nightmare.
I just use their servers, it’s encrypted anyways and my bookmarks are all public websites, so other than some data on what I like to bookmark there’s not much there.