Envira Gallery, the software I use on my wordpress website to handle my images has the option to go beyond the boundaries of a particular page of images when viewing them in Lightbox (ie. you clicked on one of the images on the page of 12, see it on it’s own and larger, and can navigate through the images via swiping if on a phone, or by keyboard left and right arrows if on a computer.
I’ve now selected that option so that you can now see all the images from a particular gallery without having to change pages – handier.