Error when I am trying to debug a jQuery script locally

I am trying to debug a script using WebStorm 8.0 debug feature but the IDE does not seem to connect to the browser.
The browser (chrome) error I am getting in the browser javascript console is the following :

Failed to load resource: the server responded with a status of 404 (Not Found) http://localhost:63342/JqueryProject2/js/jquery-1.11.1.min.js.map
Failed to load resource: the server responded with a status of 404 (Not Found) http://localhost:63342/JqueryProject2/js/jq-ajax.js.map

Why does this page tries to access these map files?

Here is the source code of the script :

$('nav a').on('click', function(e) {
    e.preventDefault();

    var url = this.href;                                //URL to load
    var $content = $('#content');                       //Cache selection

    $('nav a.current').removeClass('current');          //Update links
    $(this).addClass('current');
    $('#container').remove();                           //Remove content

    $.ajax({
        type: "POST",                                   //GET or POST
        url: url,                                       //Path to file
        timeout: 20000,                                  //Waiting time
        beforeSend: function() {
            $content.append('<div id="load">Loading</div>');    //Load message
        },
        complete: function() {                                  //Once finished
            $('#loading').remove();                             //Clear message
        },
        success: function(data) {                               //Show content
            $content.html($(data).find('#container')).hide().fadeIn(400);
        },
        fail: function() {                                      //Show error msg
            $('#panel').html('<div >Pleae try again soon.</div>');
        }
    });
});