Properties Panel absent at startup

The properties panel, and and all the other panels nested in the window with it, has recently become absent and I have to start it with the properties command with each launch. I’m sure there’s a way to save the UI to keep it present, but if so I’ve forgotten.

Hello- with one Rhino open, I would run testResetWindowPositions, then arrange as you like, close and re-open - any better?

-Pascal

Fixed it for acouple of days, but it’s back.
Doing the same fix again. Maybe I’m absent mindedly closing the properties panel (it’s undocked and on a second monitor) sometimes before I quit the programme.

This time it didn’t work.