Inputs like textboxes and checkboxes work extremely slow in the bootstrap modals. When user types some text, cursor is moving but the letters appear only in several seconds. The same behavior with checkboxes, checked/unchecked state changes only in several seconds. Can be reproduced only IE8 and Vista machine. does anybody has an idea why it happens.
here is a video with an example. you can try it here in the login dialog.
not 100% why, but ie8 has extreme problems rendering sites using position:fixed in their layout process. on random element(s), position:fixed shouldn't be too much of a problem, but typically when this issue arises it is because it is being applied to elements that are used as wrappers or containers, that usually are full of content.
for whatever reason(s), ie8 has a mighty difficult time rendering here...its best described as delayed response(s), where the user isn't sure if they actually interacted with the site, because nothing happens after their action(s).
changing fixed to absolute is the best answer in these cases, most of the time. i know there are situations where this will not apply, but everytime i've faced this issue, the element(s) had wrapper element(s) with position:relative set, and swapping out absolute for fixed could not have been easier.
ideally for me, is to serve up the different setting in conditional comments, which also is quite useful just in case changing from fixed to absolute breaks something(s)...you can target them in ie(s) and ie(s) alone with the cc's.