Before/After effect in Javascript using jQuery

Sometimes you need a simple tool to visually show the difference between two images and a basic jQuery plugin is quite suited for that (if you can stomach ~89KB just for jQuery, ~30KB if you gzip it but you probably already have it on your site, especially if you’re running Wordpress ). There are better ways to implement this, someone might suggest React or Vue or Angular or assembler or running it on the blockchain or in the bootloader but this is how I did it.
A jQuery-less version would be quite easy to implement too, perhaps in a future post.