Once you've switch to another brush tool like the Eraser or the Smooth tool brush, or switch back to the Brush tools, no brush is selected in the Brushes panel. The only way to modify the brush you're using is clicking on the button "More" in the contextual options at the top. And it doesn't display more than in my screenshot. …unless you keep it open and select another brush: this time, it's displaying the same informations as modifying a brush from the Brush panel. It's a bug, not th