Document initialization of multiple browse jQuery plugin

cookbook/usage_requirements.rst.inc

@@ -16,7 +16,7 @@ or just include the provided Twig template:
 
     {% include '@NetgenContentBrowser/page_head.html.twig' %}
 
-All HTML code blocks which have ``js-input-browse`` CSS class will be automatically initialized
+All HTML code blocks which have ``js-input-browse`` or ``js-multiple-browse`` CSS class will be automatically initialized
 on document ready with jQuery and the plugin which are included in ``netgen-content-browser.js``.
 
 If you use another CSS class, or if you add content browser HTML code via AJAX to your page,
@@ -25,4 +25,5 @@ you will need to manually initialize the plugin on those elements:
 .. code-block:: javascript
 
     // ngc_jquery variable holds jQuery included with Netgen Content Browser
-    ngc_jquery('.js-input-browse').input_browse();
+    ngc_jquery('.js-input-browse').input_browse(); // for single item select
+    ngc_jquery('.js-multiple-browse').multiple_browse(); // for multiple item select