Can I customize the content that is in the widget popup?

Unfortunately, customizing the Lightbox video popup is currently not possible through our site. The same fields that you have chosen to display in the widget cards/list will also show in the popup.

You could use CSS to hide items if needed.

If you have a developer working on your site, they could utilize the JSON API feed to develop your own display and popups. If you go with this route, you'd be able to fully customize how the display looks.