Prevent IE from generating unwanted clicks on the body. When mousedown fires on the selection element and then mouseup fires on the mask (because it is moved under the mouse during mousedown) then IE fires a click event on the body because it is the closest common ancestor. To prevent this, we detach and reatach the elements on mousedown which cancels the click event.

select2.js

@@ -105,6 +105,14 @@ the specific language governing permissions and limitations under the Apache Lic
     nextUid=(function() { var counter=1; return function() { return counter++; }; }());
 
 
+    function reinsertElement(element) {
+        var placeholder = $(document.createTextNode(''));
+
+        element.before(placeholder);
+        placeholder.before(element);
+        placeholder.remove();
+    }
+
     function stripDiacritics(str) {
         var ret, i, l, c;
 
@@ -1296,6 +1304,9 @@ the specific language governing permissions and limitations under the Apache Lic
                 mask.hide();
                 mask.appendTo(this.body());
                 mask.on("mousedown touchstart click", function (e) {
+                    // Prevent IE from generating a click event on the body
+                    reinsertElement(mask);
+
                     var dropdown = $("#select2-drop"), self;
                     if (dropdown.length > 0) {
                         self=dropdown.data("select2");
@@ -2048,6 +2059,8 @@ the specific language governing permissions and limitations under the Apache Lic
             }));
 
             selection.on("mousedown touchstart", this.bind(function (e) {
+                // Prevent IE from generating a click event on the body
+                reinsertElement(selection);
 
                 if (!this.container.hasClass("select2-container-active")) {
                     this.opts.element.trigger($.Event("select2-focus"));