I know OP personally and have a high regard for him. His blog at https://www.ctrlc.hu/~stef/blog/ is also worth following.
but the fast moving world of browser extensions made maintenance (for a non-commercial free software side project) too expensive, so the extension support became erratic, until it died completely. for a year or two i didn't use it.
but then asked asciimo if he could have a look a the extensions (since he was recently working on another extension, so had some experience), he looked at it, and rewrote the whole thing in go and fixed the extension. he even got support from nlnet/ngi0.
if you want to have your own self-hosted libre software bookmarking service for you and your community, give it a go, it's very simple, privacy respecting and most robust when it comes to snapshotting. asciimoo did a great job.