t all characters not allowed in a locale name.   
[ _make_clickable_rel_attr() ](https://developer.wordpress.org/reference/functions/_make_clickable_rel_attr/) ` wp-includes/formatting.php ` |  Helper function used to build the “rel” attribute for a URL when creating an anchor using [ make_clickable() ](https://developer.wordpress.org/reference/functions/make_clickable/) .   
[ wp_internal_hosts() ](https://developer.wordpress.org/reference/functions/wp_internal_hosts/) ` wp-includes/link-template.php ` |  Returns an array of URL hosts which are considered to be internal hosts.   
[ wp_theme_has_theme_json() ](https://developer.wordpress.org/reference/functions/wp_theme_has_theme_json/) ` wp-includes/global-styles-and-settings.php ` |  Checks whether a theme or its parent has a theme.json file.   
[ wp_img_tag_add_decoding_attr() ](https://developer.wordpress.org/reference/functions/wp_img_tag_add_decoding_attr/) ` wp-includes/deprecated.php ` |  Adds ` decoding ` attribute to an ` img ` HTML tag.   
[ wp_required_field_message() ](https://developer.wordpress.org/reference/functions/wp_required_field_message/) ` wp-includes/general-template.php ` |  Creates a message to explain required form fields.   
[ wp_required_field_indicator() ](https://developer.wordpress.org/reference/functions/wp_required_field_indicator/) ` wp-includes/general-template.php ` |  Assigns a visual indicator for required form fields.   
[ wp_preload_resources() ](https://developer.wordpress.org/reference/functions/wp_preload_resources/) ` wp-includes/general-template.php ` |  Prints resource preloads directives to browsers.   
[ WP_REST_Server::get_json_encode_options() ](https://developer.wordpress.org/reference/classes/wp_rest_server/get_json_encode_options/) ` wp-includes/rest-api/class-wp-rest-server.php ` |  Gets the encoding options passed to [ wp_json_encode ](https://developer.wordpress.org/reference/functions/wp_json_encode) .   
[ WP_Theme_JSON_Resolver::get_block_data() ](https://developer.wordpress.org/reference/classes/wp_theme_json_resolver/get_block_data/) ` wp-includes/class-wp-theme-json-resolver.php ` |  Gets the styles for blocks from the block.json file.   
[ WP_Site_Health::available_object_cache_services() ](https://developer.wordpress.org/reference/classes/wp_site_health/available_object_cache_services/) ` wp-admin/includes/class-wp-site-health.php ` |  Returns a list of available persistent object cache services.   
[ WP_Site_Health::get_page_cache_headers() ](https://developer.wordpress.org/reference/classes/wp_site_health/get_page_cache_headers/) ` wp-admin/includes/class-wp-site-health.php ` |  Returns a list of headers and its verification callback to verify if page cache is enabled or not.   
[ WP_Site_Health::check_for_page_caching() ](https://developer.wordpress.org/reference/classes/wp_site_health/check_for_page_caching/) ` wp-admin/includes/class-wp-site-health.php ` |  Checks if site has page cache enabled or not.   
[ WP_Site_Health::get_good_response_time_threshold() ](https://developer.wordpress.org/reference/classes/wp_site_health/get_good_response_time_threshold/) ` wp-admin/includes/class-wp-site-health.php ` |  Gets the threshold below which a response time is considered good.   
[ WP_Site_Health::should_suggest_persistent_object_cache() ](https://developer.wordpress.org/reference/classes/wp_site_health/should_suggest_persistent_object_cache/) ` wp-admin/includes/class-wp-site-health.php ` |  Determines whether to suggest using a persistent object cache.   
[ WP_Site_Health::get_test_persistent_object_cache() ](https://developer.wordpress.org/reference/classes/wp_site_health/get_test_persistent_object_cache/) ` wp-admin/includes/class-wp-site-health.php ` |  Tests if the site uses persistent object cache and recommends to use it if not.   
[ IXR_Message::parse() ](https://developer.wordpress.org/reference/classes/ixr_message/parse/) ` wp-includes/IXR/class-IXR-message.php ` |   
[ _register_remote_theme_patterns(