Open pop on click of custom action and get filled data I created a new custom action.

A new button is added in getAvailableActions() as we can se in below screenshot in red marked rectangle, now when i click on that button 
 (Cusotm Action) i want to open a pop up box ( i used Default pop up js lib.



Template File path : /craft/plugins/tagmanager/templates/_mergetags.twig

{% includeJsResource "tagmanager/js/tagmanager.js" %}

    &lt;div class="btn menubtn btnMeregeTags" role="button"&gt;{{ "Merge Tags"|t }}&lt;/div&gt;
    &lt;div class="menu"&gt;
    &lt;div id="mergetags-modal" class="modal"&gt; 
        &lt;div id="modal" class="body"&gt;
            &lt;header class="header"&gt;
                &lt;h2&gt;Modal header&lt;/h2&gt;
            &lt;/header&gt;
        &lt;/div&gt;
    &lt;/div&gt;
    &lt;/div&gt;


js part

$(function () {
  $modal = new Garnish.Modal($('#mergetags-modal')); //create a new modal
  $modal.show();
});




Not able to open pop up correctly.

Thank you.
I'm not sure what your Question is exactly and what your expected outcome is but to create a Modal you can use this HTML

&lt;div id="my-awesome-modal" class="modal"&gt;
    &lt;div id="modal-body" class="body"&gt;
        &lt;header class="header"&gt;
            &lt;h2&gt;My Awesome Modal&lt;/h2&gt;
        &lt;/header&gt;
    &lt;/div&gt;
&lt;/div&gt;


and via JavaScript you can show it

//create it
var modal = new Garnish.Modal($('#my-awesome-modal')); 
modal.show();