ivaynberg/select2 — pull request #2825 by xavadu (2014-11-24 14:42:38+00:00)
Title: Result open and intermediately close on change .select2-drop

The problem is that on mousedown an element is selected, when the dropdown is open under the 'select' element (where you click to open the dropdown), the mouse pointer is over the dropdown then on release the mouse click the element over the mouse pointer is selected.

https://github.com/ivaynberg/select2/issues/2823