Bug 218330

Created attachment 412633 [details] testcase with and without caption When you use position:sticky; top:0; on a table element, you expect this element to stick to the top of the overflowing frame. This usually works, unless you also have a <caption> element on your table. The caption elements have rather unique box model behavior, which introduces an offset that the sticky headers accidentally use as well. I'm not entirely sure if this is per the current specification or not. I do know that it doesn't match my expectations, and it doesn't match the behavior of Chrome and Firefox. I have included a reproduction of this problem showing behavior with and without caption element in a table.