How can I remove an object's fill?

I applied a fill to an object (a closed path). I am unable to remove the fill.  

I select the object. I activate the Interactive Fill Tool from the toolbar. When I click the "Remove the fill" button on the contextual toolbar across the top, nothing happens. The object is not locked.

In the "Objects" inspector, when I right-click to delete items that are not locked, again nothing happens. Using the Trash icon at the bottom of the inspector sometimes works, but not always.

These banal tasks should be simple and intuitive, so I am wondering if I am not dealing with bugs (and yes, I realize that maybe I am doing something wrong). The documentation and tutorials I could find were based on the Windows version.  But you can imagine what goes through a new user's mind having used several other apps: is CD on macOS a viable option?

Being able to see only one inspector window at a time is also very inefficient.

Is anyone else feeling my pain?

Thank you all!