.data() reads a data- attribute the first time it is asked and then caches the value in jQuery’s own store, keyed off an expando property on the element.…
Sizzle hands a selector to querySelectorAll whenever the browser has it, and IE8 does — for CSS 2.1 selectors only. Anything from CSS3 or invented by jQuery makes…
jQuery split these in 1.6 and the change is still working its way through everyone’s habits, because attr(‘checked’) kept doing roughly the right thing for years. An attribute…