Snoop is the open source WPF spying utility. It allows you to spy/browse the visual tree of a running WPF application (without the need for a debugger) … and change properties ... amongst other things.

Snoop is the open source WPF spying utility created by Pete Blois and now maintained by Team Snoop (Cory Plotts, Dan Hanan, Andrei Kashcha, and Maciek Rakowski).

It allows you to spy/browse the visual tree of a running WPF application (without the need for a debugger) … and change properties... amongst other things.