title: React dropzone uploader extra.reject, dropzoneReject not working for custom extension other than MIME types in accept
body: <p>I have been using react-dropzone-uploader I am passing accept prop as below</p>
  
  <pre><code>accept=".glb"
  </code></pre>
  
  <p>for this extension, extra.reject in "inputContent" function always returns false when dropping other format files.
  but when I pass the proper MIME types like below</p>
  
  <pre><code>accept="image/*,audio/*,video/*"
  </code></pre>
  
  <p>it is returning extra.reject as true when dropping other format files.</p>
  
  <p>just wondering if there is any workaround to trigger "extra.reject" to be true when other format files are dropped when I give the custom extension.</p>