Example
WP_DEBUG_DISPLAY is another companion to WP_DEBUG that controls whether debug messages are shown inside the HTML of pages or not. The default is 'true' which shows errors and warnings as they are generated. Setting this to false will hide all errors. This should be used in conjunction with WP_DEBUG_LOG so that errors can be reviewed later.
Note: for WP_DEBUG_DISPLAY to do anything, WP_DEBUG must be enabled (true).
//enable
define( 'WP_DEBUG_DISPLAY', true );
//disable
define( 'WP_DEBUG_DISPLAY', false );
