It was a while ago when I had my SpaceNav 3D mouse working in FreeCAD with buttons and it’s a natural feel now but for some reason my button assignments wen’t there with the latest release.
I went to set them up, only 2 buttons, but they were handy for snapping the view to Fit Window and IIRC Front View. For some reason I can’t get those options in the current Customize Space Mouse settings.
I am getting better with keyboard hotkeys so will just have to use that unless someone else knows more. These pucks are really quite nice for 3D nav.
Solution: I had to select “SpaceNavigator” as the device in the lower left of the Customizer window and then it the reset button. At that point it created 2 buttons in the left pane and when selected, a different group of options on the right appears. Plenty of options from the View menu so I was able to select “Fit All” for button 1 and Front for button 2.