Pop-up all images (again)

Plone Support Theming
1

(I used to have a solution for this, but with 5.1 I can not get it to work anymore)

How can I have all images to open in an overlay if I click on them

I used to do:

<script type="text/javascript">
  $(function($){
  $('#content-core img').prepOverlay({subtype: 'image'});
 })
</script>