I was looking for a lightbox popup script with the following attributes
- compatibility across browsers
in that order, and found everything I wanted in Easy Fancybox, PLUS
- a percentage based popup dimension mechanism
- resizing larger images to browser.
- opening pdfs
At the beginning I thought I'd better try "lighter" Slimbox based lightboxes but I had a lot of issues with different browsers and different image sources & I was giving up features
Easy Fancybox covered all my needs in the best possible way.