The top bar widget area sits on top of your header, and can hold as many widgets as you like.
You can find the widget area in Appearance > Widgets or Customize > Widgets.
In order for the below Customizer settings to appear, you must have at least one widget in the area.
Adjusting the layout
The top bar has a few layout settings which you can find in Customize > Layout > Top Bar.
Top Bar Width
Choose whether the outer container is full width or contained.
Top Bar Inner Width
Choose whether the inner container is full width or contained.
Top Bar Alignment
The initial alignment of your widgets. The widgets try to even themselves out for you.
If the alignment is set to left, the first widget you add will be on the left, the second widget you add will be on the right, the third widget you add will align back to the left and so on.
Spacing
The Spacing add-on adds four padding options to the widget area so you can choose the top, right, bottom and left padding. These options are also found in Customize > Layout > Top Bar.
Colors
The Colors add-on adds all of the color options you need for your widget area in Customize > Colors > Top Bar.
Background Images
The Backgrounds add-on adds all of the background image options you need in Customize > Background Images > Top Bar.
Secondary Navigation
If your secondary navigation is also set to be above the header, an option to merge the top bar widget area and secondary navigation is added in Customize > Layout > Top Bar.