Visually diff 2 webpages.
Uses CSS mix-blend-mode to visually diff 2 webpages. Enter a second page's url to compare it against the currently open tab. Black equals no difference (two identical pages will result in a completely black page).
- (2021-04-06) Adam Laughlin: Some bugs, like hitting compare twice reloads the page, and enter doesn't submit the form. Otherwise, the best tool (and only one we could find) for visually comparing two pages (or two versions of the same page).