In most cases, the Meow Lightbox should work right away.
Demo
Click on one of those images, and you’ll see the Meow Lightbox. Try also clicking on an image, then reloading the page. The same image will show up!
Usage
Selector
By default, the selector is set on:
.entry-content, .gallery, .mgl-gallery, .wp-block-gallery
This selector represents the CSS elements (separated by commas) in which the lightbox will look for images and does its magic. Depending on the theme, or what you exactly need, the selector might be different. If you are using the galleries in WooCommerce for example, you should this to your selector (with a comma).
.woocommerce-product-gallery
Check the FAQ below if you are confused.
Anti Selector
Sometimes, the selector catches too many images and you want specific pages, galleries or photos to be skipped by the Lightbox. You can do this with the Anti Selector.
In my settings, I set the Anti Selector to ‘.mgl-square’. This CSS class is used by the Meow Gallery for the Square layout, like above. Even the Lightbox should work on it via the Selector, the Anti Selector will void it.