1506926 - Consider optimizing the way pixel difference is calculated for color contrast highlighter.

Status: NEW

(DevTools :: Accessibility Tools, enhancement)

Description

[Yura Zenevich [:yzen] (please use "needinfo")]

The tool can get slow if we have a lot of pixels to go through.
On a big text node (font-size: 100em, or smaller but with a text-shadow) I could see a noticeable freeze on my machine.

One solution could introduce an upper bound (either for this loop or for the size of the window "screenshot" we take).

Another solution could be scaling the image to something smaller, it will probably still yield reasonable results.