The idea is to ask an AI interface questions and search for the answers in the websites stored in the bookmarks. You could also search just a part of the bookmarks, such as tags, folders or containers.
This approach allows you to use your bookmarks as your personal knowledge base. I think this would be very useful for research, but also for private use cases. Maybe the answers you are looking for are already in the combined text body of your favorites?
(In order to be able to check the answers, it would be useful to indicate the source, as Perplexity.ai does).
That way, bookmarks become much more valuable than just a historical documentation of some more or less valuable gems you found on the Internet. At least I think so.