What's out:
* 6 KB
* attribute not equal selector
* positional selectors (:first; :eq(n); :odd; etc.)
* type selectors (:input; :checkbox; :button; etc.)
* state-based selectors (:animated; :visible; :hidden; etc.)
* :has(selector)
* custom selectors
* leading combinators (e.g., $collection.find("> *"))
* reliable functionality on XML fragments
* requiring all parts of a selector to match elements under context (e.g., $div.find("div > *") now matches children of $div)
* matching against non-elements
* reliable sorting of disconnected nodes