Registers a selection of default headers to be displayed by the custom header admin UI.

Registers a directory that contains themes.

Registers a theme feature for use in add_theme_support().

Removes all visual editor stylesheets.

Removes theme modification name from active theme list.

Removes theme modifications option for the active theme.

Allows a theme to de-register its support of a certain feature

Checks a theme’s support for a given feature before loading the functions which implement it.

Searches all registered theme directories for complete and valid themes.

Updates theme modification value for the active theme.