title: Gallery with custom handlers are not working in fancybox V4
body: <p>I was trying to create gallery with fancybox v4.0.5, It is working perfectly with default handler but with custom, model is opening but slider is not working.</p>
  <h1>Here is the code===</h1>
  <pre><code>&lt;link rel=&quot;stylesheet&quot; href=&quot;https://cdn.jsdelivr.net/npm/@fancyapps/ui@4.0/dist/fancybox.css&quot; /&gt;
  &lt;script src=&quot;https://cdn.jsdelivr.net/npm/@fancyapps/ui@4.0/dist/fancybox.umd.js&quot;&gt;&lt;/script&gt;
  &lt;div class=&quot;grid imglist&quot;&gt;
      &lt;div class=&quot;row padding-bottom--sm&quot;&gt;
          &lt;a class=&quot;col col--4&quot; data-custombox=&quot;demo&quot; data-src=&quot;https://lipsum.app/id/1/1024x768&quot; data-caption=&quot;&lt;b&gt;Hello, There!&lt;/b&gt; &lt;br /&gt; This is a multi-line caption&quot;&gt;&lt;img src=&quot;https://lipsum.app/id/1/400x300&quot;&gt;&lt;/a&gt;
          &lt;a class=&quot;col col--4&quot; data-custombox=&quot;demo&quot; data-src=&quot;https://lipsum.app/id/2/1024x768&quot; data-caption=&quot;Optional caption&quot;&gt;&lt;img src=&quot;https://lipsum.app/id/2/400x300&quot;&gt;&lt;/a&gt;
          &lt;a class=&quot;col col--4&quot; data-custombox=&quot;demo&quot; data-src=&quot;https://lipsum.app/id/5/1024x768&quot;&gt;&lt;img src=&quot;https://lipsum.app/id/5/400x300&quot;&gt;&lt;/a&gt;
      &lt;/div&gt;
      &lt;div class=&quot;row&quot;&gt;
          &lt;a class=&quot;col col--6&quot; data-custombox=&quot;demo&quot; data-src=&quot;https://lipsum.app/id/3/1024x512&quot;&gt;&lt;img src=&quot;https://lipsum.app/id/3/500x250&quot;&gt;&lt;/a&gt;
          &lt;a class=&quot;col col--6&quot; data-custombox=&quot;demo&quot; data-src=&quot;https://lipsum.app/id/4/1024x512&quot;&gt;&lt;img src=&quot;https://lipsum.app/id/4/500x250&quot;&gt;&lt;/a&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  &lt;script&gt;
  $(window).load(function() {
      Fancybox.bind(&quot;[data-custombox]&quot;, {});
  })
  &lt;/script&gt;
  </code></pre>