Compare images - highlight differences/same parts

[gendalf]

Add a checkmark/button to highlight differences between images
Add a flip to inversely single out differences instead (color the rest of the image with the same color for example)
Add a detection (sensitivity) slider
kinda like imagemagick https://www.imagemagick.org/Usage/compare/

useful for example in comparing quality of the same picture from different sources/formats or screenshots from the same video but differently encoded