If you need an extra level of de-bugging when testing your Wordpress site, or simply need more specific error information on top of that produced in the error logs, then Wordpress has a constant (a permanent global variable) that can be set to output the information to the browser.
To enable this setting you will need to add the following line to the wp-config.php file which can be found in the default directory that Wordpress is installed to:
define('WP_DEBUG', true);
This can be added anywhere within the file. Save the change once made and this will then activate the setting meaning all PHP errors, notices and warnings will be displayed in your browser.
*** It is not recommended to use this setting with a live site as this can lead to vulnerabilities with the code being identified by anyone visiting the site so don't forget to set this back to false once you are done de-bugging. ***
