I think this AO3 filtering trick deserves more attention

Unfortunately the tag filtering on AO3 still doesn't have an easy way to exclude stories with certain tags, but I didn't realize that you can use a - with the "Search Within Results" in the sidebar to narrow things down and not only in the full search. (I almost never use the full AO3 search, I dislike it.)

And even better, you can (in an admittedly somewhat tedious way) exclude wrangled relationship tags by their id, so that you don't exclude text matches in the summary accidentally. This archive news post describes how. I won't use this for casual searches, but it is worth looking up the ids of the few pairings I really loathe to get them excluded in all my searches. And apparently there is an unofficial userscript for this too, so maybe I'll install that... Right now I use a blurb blocker to filter, but it would be more efficient to get the search right rather than hide results.