Bookmarks definitely sync with Firefox sync. I have the same bookmarks on all of my devices.
Extension settings can sync, I don't know exactly if it is opt-in or opt-out but some extensions do sync on desktop. The mobile situation is definitely different, mobile doesn't sync to desktop. I don't know if different mobile devices sync with each other (I only have one).
Yeah, search engines don't which is annoying and confusing. However on desktop you can use keyword bookmarks which offer basically the same functionality and do sync.
uBlock Origin does it's own weird thing where you need to trigger the sync in the settings interface. I don't think you can blame Firefox for this UX choice.
> However on desktop you can use keyword bookmarks which offer basically the same functionality and do sync.
Search engines can have completion; keyword bookmarks can't. Most search engines don't support it, but some do.
> uBlock Origin does it's own weird thing where you need to trigger the sync in the settings interface. I don't think you can blame Firefox for this UX choice.
It made the same choice in Chrome, so I was familiar with that. It works there, it doesn't work on Firefox. I think it's fair to put that on Firefox.
Extension settings can sync, I don't know exactly if it is opt-in or opt-out but some extensions do sync on desktop. The mobile situation is definitely different, mobile doesn't sync to desktop. I don't know if different mobile devices sync with each other (I only have one).