Show Filenames in Lightbox only from Grid Gallery

Hi all,

I'm wondering if there's a way to code for showing file names (not captions) when photos are opened in a lightbox from a grid gallery.

My client has hundreds of family photos, all named appropriately (i.e., Andy_1962.jpg) and they want the file name to show when opened in the lightbox, but not on the grid.

I tried the below code, but it didn't work. Any insight?

Header injection:

<script src="https://code.jquery.com/jquery-3.6.0.min.js" integrity="sha384-vtXRMe3mGCbOeY7l30aIg8H9p3GdeSe4IFlP6G8JMa7o7lXvnz3GFKzPxzJdPfGK" crossorigin="anonymous"></script>
<script>
  window.Squarespace.onInitialize(Y, function(){
    $('.slide img').each(function(i) {
      $('.image-slide-title').eq(i).html('' + $(this).attr('alt').replace('.jpg', '') + '');
    });
  });
</script>

CSS:

.sqs-gallery-block-grid.sqs-gallery-block-meta-only-title .margin-wrapper .image-slide-title {
  line-height: 1.2em;
  white-space: pre-wrap;
  overflow: visible;
}

Thanks!

Mary Alice 

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