First item clicked on menu opens page in new tab

First item clicked on menu opens page in new browser tab. Afterwards, if I use the new tab, all works as expected (no new browser tab. How can I prevent that initial new tab creation (reproduced in IE, Chrome, Firefox)?

Any assistance will be appreciated.

My code (required xml file at the end):

<?php include_once("phpheader.php") ; include_once("activityhtmlheader.php"); ?>
<script>
    document.title="Welcome";

    var dhxWins= new dhtmlXWindows();
    var win = dhxWins.createWindow("main_window", 0, 0, 800, 600);
    dhxWins.window("main_window").maximize();
    dhxWins.window("main_window").button("park").hide();
    dhxWins.window("main_window").button("stick").hide();
    dhxWins.window("main_window").button("sticked").hide();
    dhxWins.window("main_window").button("help").hide();
    dhxWins.window("main_window").button("minmax1").hide();
    dhxWins.window("main_window").button("minmax2").hide();
    dhxWins.window("main_window").button("close").hide();
    dhxWins.window("main_window").button("dock").hide();
    dhxWins.window("main_window").hideHeader();
    dhxWins.setSkin('dhx_skyblue');

    menu = dhxWins.window("main_window").attachMenu();
    menu.setIconsPath("");
    menu.loadXML("./activities_menu_links.xml?etc="+new Date().getTime());

    tabbar = dhxWins.window("main_window").attachTabbar();
    tabbar.setSkin('dhx_skyblue');
    tabbar.setImagePath("dhtmlxSuite/dhtmlxTabbar/codebase/imgs/");///dhx_skyblue/dhx_skyblue_top.gif
    tabbar.addTab("a1","Welcome","150px");

    var addFormLayout = tabbar.cells("a1").attachLayout("2U","dhx_skyblue");
    addFormLayout.cells("a").setText("Help");
    addFormLayout.cells("b").setText("Information and Announcements");
    addFormLayout.cells("a").attachURL("./help/1/1.html");

    tabbar.setTabActive("a1");

    tabbar.attachEvent("onTabClose",function(){
        return true;
    });
    tabbar.attachEvent("onSelect",function(name){
        return true;
    });



    <?php if($_SESSION['user_type']==1) { ?>
    formStructure = [
        {type:"settings"},
        {type:"input", name:"atext", position:'relative', labelLeft:'0', inputTop:'40', rows:'20', width:'800'},
        {type:"button", name:"btn_update_announcements", width:200,offsetTop:2, value:"Update Announcements", position:'relative', labelLeft:'0', labelTop:'470', inputLeft:'0', inputTop:'370'}
    ];
    <?php } else { ?>
    formStructure = [
        {type:"settings"},
        {type:"input", name:"atext", position:'relative', labelLeft:'0', inputTop:'40', rows:'20', width:'800'}
    ];
    <?php } ?>
    //var myForm = new dhtmlXForm("form_container",formStructure);
    myForm = addFormLayout.cells("b").attachForm(formStructure);

    var formdp = new dataProcessor("./ajax_update_announcements.php");//instatiate dataprocessor
    formdp.init(myForm);//link form to dataprocessor
    myForm.attachEvent("onButtonClick", function(id){
        myForm.send("./ajax_update_announcements.php",function(loader,response){
            alert(response);
        });
    });
    //make darn sure that you include the ?id= at the end lest you get cryptic errors
    myForm.load("./form_select_sources/announcements_selector_for_edit.php?id=");

</script>
<?php include_once("htmlfooter.php"); ?>

xml file:

<?xml version="1.0"?>

Could you provide the whole demo, please?
Send it on support@dhtmlx.com with link to this topic.
docs.dhtmlx.com/doku.php?id=othe … leted_demo

Thanks for your help. Removing the target= from my xml fixed the problem.