Hello I have a problem: Your template doesnt allow the article to save. if I click the button save, nothing happens. Its the template UNEI. In category the error doesnt happen, only in Articles.

In Console I get this if I open an article:

Uncaught TypeError: this._addClass is not a function
    jQuery 8
        _create
        t
        _createWidget
        a][t
        e.widget.bridge/e.fn[n]/<
        each
        each
        n
    <anonymous> localhost/vonfuchs-gartenbau/plugins/system/helixultimate/assets/js/admin/blog-options.js?ce560673956a0ca6c1ed581a665d4be8:7
    jQuery 8
        u
        fireWith
        ready
        _
        promise
        <anonymous>
        <anonymous>
        <anonymous>

and if I try to save (clicking the save button) I get this:

"Uncaught TypeError: document.formvalidator is null"