select2 xpages bug?: page got stuck after removing 2 or more characters

Question

I do have a weird problem. Don't know if it is a bug. I tried to fix it and find workarounds for some time but nothing works so far. I hope somebody can help me. Thank in advance.

Problem description In my select2 box i do typed some characters and i got a list of matches. After removing 2 or more characters i select a match form de list. At that moment the page got stuck. It has lost any reference. The only solution is to refresh the entire page.

The ajax call works fine, the select2 box is refreshed by every change. Pressing enter executes a onchange function (csjs). All functions seem to work because debug messages after every function are show in my java console.

My code

                        <xp:scriptBlock id="scriptBlock3">
                            <xp:this.value><![CDATA[

                var executeOnServer = function ( eventId ) {

// must supply event handler id or we're outta here....

if (!arguments[0])

    return false;

// OPTIONAL - The Client Side ID that you want to partial refresh after executing the event handler
var refreshId = (arguments[1]) ? arguments[1] : "@none";
var form = (arguments[1]) ? XSP.findForm(arguments[1]) : dojo.query('form')[0];

// OPTIONAL - Options object containing onStart, onComplete and onError functions for the call to the

// handler and subsequent partial refresh

var options = (arguments[2]) ? arguments[2] : {};

// OPTIONAL - Value to submit in $$xspsubmitvalue. can be retrieved using context.getSubmittedValue()

var submitValue = (arguments[3]) ? arguments[3] : '';

// Set the ID in $$xspsubmitid of the event handler to execute

dojo.query('[name="$$xspsubmitid"]')[0].value = eventId;

dojo.query('[name="$$xspexecid"]')[0].value = "";

dojo.query('[name="$$xspsubmitscroll"]')[0].value = "0|0";

dojo.query('[name="$$xspsubmitvalue"]')[0].value = submitValue;

XSP._partialRefresh("post", form, refreshId, options);}

x$("#{id:inputTextNieuweStudent}")
.select2({
        placeholder: "Selecteer een student",
        minimumInputLength: 3,
        quietMillis: 750,
        width: '400px',            
        ajax: {
                url: "/Apps/FEZ/SBA.nsf/selecteerStudent.xsp",  
                dataType: 'json',
                data: function (term, page) {
                return {
                    q: term, // search term
                    page_limit: 10,
                    local : true
                };
            },
            results: function (data, page) { // parse the results into the format expected by Select2.
                return data;
            }
        }

})
.on("change", 
    function(e) {
        console.log("changed to " + e.val);
        executeOnServer("#{id:voegToeStudent}", "#{id:lijstStudentSelectie}", {});
    } 
);
   ]]></xp:this.value>
                        </xp:scriptBlock>
                        </xp:inputText>