I noticed that in the unread page, if i have some "legacy" posts that is unread, and subsequently the category is disabled, it will still remain in the unread page.
However, when one clicks on the post, it will show a 404 error.
Currently watching categories is opt-out. On forums having lots of new topics, this results in a huge number of items in
example.com/unread. I think the unread page would be far more useful if watching categories was opt-in. That way
/unread would contain only the items a user is interested in from the start and they won't have to go ignore a bunch of categories in order for
/unread to become useful.