Add an A/B slider to Compare Tool

[wOLVERINe]

Hi,

The build-in Compare Tool is great but often times I need to compare images as stacked images. What works great for this are image comparisons tools that you see more often online than offline, like this one - https://themify.me/demo/themes/addon-ab-image/

It doesn't need to analyze the images. Just a simple slider AND toggle back and forth (full left, full right) shortcut would be nice.
What also would be nice is if the tool could smartly jump between filenames based on 2 files or some naming convention. So that when given the filenames below in a folder, when you press PageUp/Down (Next/Back), it grabs the next set for comparison. (01, 01) (02, 02)

01_before.jpg
01_after.jpg
02_before.jpg
02_after.jpg

[xnview]

yes will be great...