X is Twitter. You bookmark practically anything (post, comment, quote) and can find it later in one place.

I did put it together on a whim because I don't trust that something won't happen to X.com some years in the future with Elon and you legitimately cannot export your bookmarks from X. If that happens, your bookmarks will be lost.

Yes, it is a paid product because I put serious time into it and I designed it to be something I would use myself (even if I make no money off it).