`:not(.what) .ever` should be fairly fast, unless you have lots of `class="ever"` elements. Not ideal, but not as bad as e.g. `.ever :not(.what)` would be. `:ha

`:not(.what) .ever` should be fairly fast, unless you have lots of `class="ever"` elements. Not ideal, but not as bad as e.g. `.ever :not(.what)` would be. `:has()` is just inherently slow if there's a significant amount of elements to search, even though browsers have some caching and tricks. Normally, you be able to debug selector matching performance (and in general, see how much style computation costs you), so it's a bit weird if you have phantom multi-second delays.