Floating palette disappear when moving between screens

My first post! I am kicked to learn Rhino. I have 6+ years of 3D modeling experience with Alias, solidWorks and other programs.

I am using an external monitor (HDMI) and Rhino is open there. I have some floating panels open too. When I move back to my MacBook screen and want to do some business there, the floating windows in Rhino disappear.
They reappear when I click inside Rhino.

Any idea why?