ZUI Geometry Debugger

Bookmarklet that wraps any page in a zoom/pan surface and opens two panels: real-time cursor coordinates (screen + world, zoom, pan) and a geometry inspector that highlights hovered elements with bounding-box measurements. The highlight overlay updates on scroll, resize, and viewport change rather than clearing on stale data.

Note: Pages with a strict Content Security Policy that blocks import() from external origins will prevent this bookmarklet from loading.

Drag to your bookmarks bar:

Source (loaded via CDN)