ivaynberg/select2 — pull request #1874 by vitalets (2013-11-03 18:26:17+00:00)
Title: fix body leak of `click` on IE: replace mousedown with mouseup, fixes #1058

I've digged this common issue here:
http://stackoverflow.com/questions/19215427/internet-explorer-leaks-click-event-after-adding-an-overlay-in-a-jquery-mousedow/19755974#19755974