While viewing a full size image in the light box, have the corresponding thumb highlighted somehow.
That would be easier to keep track of where you are in the thumbnail strip.
Thanks
I realize that the corresponding thumb is in the center of the strip ( when the strip contains enough thumbs to extend past the container ) but that might not be obvious to a first time casual viewer.
It does actually already do that. I just double-checked in my galleries. I have it set up so that all of the thumbnails are highlighted one color, and the current one is highlighting a different one.
Look for the setting area called “Lightbox Thumbnails”, at the bottom you’ll have three different color sliders. The first one is the main color all of the thumbnails will have around it. The second one is the active color that you’re looking for.