Many years ago there used to be a Firefox extension (..or might have even been a Mozilla one..) that would store all the pages I visit. I recall its name was Breadcrumbs but I could be misremembering. Space is cheap, or at least affordable if one would exclude videos, which are probably technically more difficult to archive anyway, but sometimes one remembers having seen content that is never to be found again.

I think it would be useful to have just a personal basic search engine on that kind of contents, but possibly a RAG or even a fine tuned LLM would be even cooler.

Actually, e.g. Firefox could do that at least for its bookmarks and tabs, though it already does provide the function for tagging bookmarks. And I think there's probably an extension for searching tabs' contents..