Pixel Distance Ruler by Heizou

Pixel Distance Ruler is a lightweight Firefox addon designed for designers, UI testers, and developers. It allows you to quickly measure the pixel distance between any two points on a webpage with just two clicks. Once activated, simply click two points anywhere on the screen, and the addon will instantly display the straight-line distance in pixels. It's a simple yet powerful tool for verifying layouts, spacing, and alignment without opening DevTools.