So I’m not suggesting a big change, just making the header and side regions have a small amount of opacity rather than zero on the default theme.
So for the header it better shows that there is something there and it isn’t just gone. If the impression is that something does not exist at all then you wouldn’t ask the question “how do I make it look different”.
Similarly, the side tool region clearly shows an edge and therefore would make sense when the mouse pointer changes into one for “resizing”.
Once you know how to change theme preferences it can look how you like, but you’ve already learned two lessons: the header exists but can have a color and transparency. And that the side panel extends to the bottom. If you later make it invisible you still know why the mouse behaves as it does there.
