For the installed (that is, integrated, not a Stack) photo gallery, is there a setting which will permit the expansion of an image when a user clicks a thumbnail? I can’t find it.
Within the settings for the Photo Album page there is a default of Album Type: Slideshow
Change that to Album Type: Gallery
When you preview you get a very basic lightbox with controls for home, next and previous.
Tried that. Unless the functionality doesn’t work in preview mode, this method doesn’t work.