Title: 3.1.3 | Developer.WordPress.org

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# New and updated in 3.1.3

Functions

Hooks

Classes

Methods

 * function[sanitize_mime_type()](https://developer.wordpress.org/reference/functions/sanitize_mime_type/)
 * Sanitizes a mime type
 * Used by [0 functions](https://developer.wordpress.org/reference/functions/sanitize_mime_type/#used-by)
   | Uses [1 function](https://developer.wordpress.org/reference/functions/sanitize_mime_type/#uses)
   | Source: [wp-includes/formatting.php:5800](https://github.com/WordPress/wordpress-develop/blob/7.1/src/wp-includes/formatting.php#L5800-L5811)
 * hook[sanitize_mime_type](https://developer.wordpress.org/reference/hooks/sanitize_mime_type/)
 * Filters a mime type following sanitization.
 * Used by [1 function](https://developer.wordpress.org/reference/hooks/sanitize_mime_type/#used-by)
   | Uses [0 functions](https://developer.wordpress.org/reference/hooks/sanitize_mime_type/#uses)
   | Source: [wp-includes/formatting.php:5810](https://github.com/WordPress/wordpress-develop/blob/7.1/src/wp-includes/formatting.php#L5810-L5810)
 * function[send_frame_options_header()](https://developer.wordpress.org/reference/functions/send_frame_options_header/)
 * Sends a HTTP header to limit rendering of pages to same origin iframes.
 * Used by [0 functions](https://developer.wordpress.org/reference/functions/send_frame_options_header/#used-by)
   | Uses [0 functions](https://developer.wordpress.org/reference/functions/send_frame_options_header/#uses)
   | Source: [wp-includes/functions.php:7282](https://github.com/WordPress/wordpress-develop/blob/7.1/src/wp-includes/functions.php#L7282-L7287)
 * function[is_protected_meta()](https://developer.wordpress.org/reference/functions/is_protected_meta/)
 * Determines whether a meta key is considered protected.
 * Used by [11 functions](https://developer.wordpress.org/reference/functions/is_protected_meta/#used-by)
   | Uses [1 function](https://developer.wordpress.org/reference/functions/is_protected_meta/#uses)
   | Source: [wp-includes/meta.php:1312](https://github.com/WordPress/wordpress-develop/blob/7.1/src/wp-includes/meta.php#L1312-L1327)
 * function[sanitize_meta()](https://developer.wordpress.org/reference/functions/sanitize_meta/)
 * Sanitizes meta value.
 * Used by [4 functions](https://developer.wordpress.org/reference/functions/sanitize_meta/#used-by)
   | Uses [2 functions](https://developer.wordpress.org/reference/functions/sanitize_meta/#uses)
   | Source: [wp-includes/meta.php:1342](https://github.com/WordPress/wordpress-develop/blob/7.1/src/wp-includes/meta.php#L1342-L1378)