Widgets are interactive objects which are rendered inside the content view. Widgets can be rendered in different positions, called Widget Areas.
Widgets may have the form of buttons, labels, menus, etc. They can be used to clarify something to an author, or to assist them otherwise.
Widget areas can be set to null to omit the area and any space reserved for it. Setting an area to an empty array instead reserves space where appropriate without rendering any widgets. This can be used, for example, to render a consistent margin for elements where some display widgets in the
blockOutsideBefore area and others do not.