Height matching chooser?

I upgraded to WM 3.0 (woo, mimic and scatter!) but I don’t see a device called ‘Height matching chooser’ anywhere? Is that an actual device or just the existing height chooser from 2.9? The description on the 3.0 page says

Height-Matching Chooser
Lets you combine together two different terrains or images more seamlessly.

Hi there,

Take a look inside the existing Chooser device – you’ll see it’s been re-worked slightly, with the new “Height Matching” mode added there.

Take a look at the example file “New for 2.9\Height Matching Chooser” for an example of what it does for ya!