WP_Customize_Header_Image_Setting::sanitize()
Method: Sanitizes a header value.
Source: wp-includes/customize/class-wp-customize-header-image-setting.php:98
WP_Customize_Header_Image_Setting::sanitize_choice()
Method: Sanitizes a header image choice.
Source: wp-includes/customize/class-wp-customize-header-image-setting.php:132
get_custom_header()
Function: Gets the header image data.
Source: wp-includes/theme.php:1499
is_network_only_plugin()
Function: Checks for “Network: true” in the plugin header to see if this should be activated only as a network wide plugin. The plugin would also work when Multisite is not enabled.
Source: wp-admin/includes/plugin.php:608