Retrieves the widget ID base value.

Registers the form callback for a widget.

Registers the update callback for a widget.

Compares a list of sidebars with their widgets against an allowed list.

Handle sidebars config after theme change

Display dynamic sidebar.

Determines whether a sidebar contains widgets.

Determines whether a given widget is displayed on the front end.

Determines whether the dynamic sidebar is enabled and used by the theme.

Checks if a sidebar is registered.