Hi, thank you so much for the compliment.
To create the slider there’s a built in function that allows you to do that. When you’re creating your topic hit this button, it will automatically generate the code, then all you need to do is add the two images and you’re done!
If you need more details here’s the link to the discussion: https://blenderartists.org/t/blenderartists-now-has-image-comparison-sliders/1466950