jQuery

Looks like jQuery is loaded when this option is selected “Remove numbers from comment authors”

Still – surely the functionality of that option can be accomplished without jQuery?

If you would like to provide the pure js for that then I would gladly incorporate

(function ($) {
    'use strict';

    $(document).ready(function ($) {
        $(".comment-form input[name='author']").blur(function () {
            $(this).val($(this).val().replace(/\d+/g, ''));
        });
    });

})(jQuery);