JCE MediaBox has been rebuilt as a modern, responsive lightbox extension for Joomla 3 and Joomla 4. Our goal for this version is to create an attractive and easy to use, responsive and accessible lightbox as a companion for the JCE Editor, or for use as a standalone Joomla extension.
MediaBox 2 is compatible with existing MediaBox code, and comes with updated versions of the 4 themes - Standard, Light, Shadow and Squeeze. A future version will include Bootstrap and UIKit styles.
You can see examples of MediaBox 2 here - https://www.joomlacontenteditor.net/products/jce-mediabox
A full range of tutorials on creating popups for each media type is available here
JCE MediaBox is a free download. Forum based support is provided with a JCE Pro Subscription.