DotNetNuke 9 dnnConfirm dialog error

It seems that since DotNetNuke 9 the build-in confirm dalog dnnConfirm does not work anymore like it did before or has been removed. The error is Uncaught TypeError: $(...).dnnConfirm is not a function

I uses it like this

<script type="text/javascript">
    $('.DeleteButton').each(function (index, item) {
        $(this).dnnConfirm({
            text: 'Delete this item?',
                yesText: 'Yes',
                noText: 'No',
                title: 'Delete Dialog',
                width: 400,
                isButton: false
            });
        });
</script>

I looked it up in the documentation, but could not find anything.

• http://www.dnnsoftware.com/wiki/dnnconfirm-jquery-plugin
• http://uxguide.dotnetnuke.com/UIPatterns/ConfirmDialog.html

Does anyone have a fix/workaround/solution?

UPDATE

I just found out the function is present when you log in as a SuperUser but not as a visitor or normal user who is logged in. This would indicate that some JS files are only loaded when SuperUser whereas they were always present in previous versions.

The problem has been identified and a solution has been found. The file that was missing on the client side was dnn.jquery.js. In older versions of DNN (< 7.3) it was added by calling DotNetNuke.Framework.jQuery.RequestDnnPluginsRegistration(); in code behind.

But since version 7.3 it has been replaced with JavaScript.RequestRegistration

using DotNetNuke.Framework.JavaScriptLibraries;

protected void Page_Load(object sender, EventArgs e)
{
    JavaScript.RequestRegistration(CommonJs.DnnPlugins);
}