Everyone to like lightbox or prettyphoto to show images in nicely in popup. In wordpress are many plugins to set popup for your images but need to insert or set rel to every images or gallery. But if you added all the images then you can decide to open image in popup that time very difficult to rework to set or edit rel in every images or gallery. If you want to set automatically rel in every images or add all gallery images rel=lightbox or something like that then this post is very useful to you and save lot of time. If you want to set all images url rel=lightbox or rel=prettyphoto then add this below function to your theme function.php file. [php] <!--?php <br ?-->// Custom functions add_filter('the_content', 'my_addlightboxrel');…