Zooming while using a polygon mask in Fusion

Intel core i7-8700K
32GB DDR4 Dual RAM
Windows 10 Pro
Davinci Resolve 17

Hi All,
I know how to zoom in using the mouse wheel, say in the colour page, to ascertain how much spill my still be present around a subject; when working to remove green screen, and then to zoom back out again. However, can any one tell me if there’s a similar zoom, just a quick in and out, when using the polygon mask in fusion? I can’t seem to find a process, anywhere?
Thanks

I think it's CTRL+scroll middle mouse button.

Sander de Regt, you are a marval; thank you, thank you, thank you