Use Examples on watchkeeper.net

Checking a Staging Site on Localhost Before It Goes Live

Fri, 23 Oct 2026 00:00:00 +0000

The best time to find out what a page sends is before it’s live. Watchkeeper opens a local copy as easily as a public site, so a developer can check a build on their own machine before anyone else loads it.

Start the staging server as usual, then point Watchkeeper at it. A local address needs its http:// written out:

watchkeeper http://localhost:8090/

Telling a Fingerprinting Script Apart From a Page Saving Its Own Chart

Fri, 23 Oct 2026 00:00:00 +0000

Reading back a canvas is the classic first step of a device fingerprint. It’s also how a page turns a chart into an image you can download. So a canvas read on its own proves nothing. What matters is who made it.

This quiz page draws a bar chart of your answers and offers it as an image, which takes one canvas read by the page’s own code. It also loads a script from a fingerprinting vendor.