$displayVars public property (available since version 2.0.7)
List of the PHP predefined variables that should be displayed on the error page. Note that a variable must be accessible via $GLOBALS. Otherwise it won't be displayed. Defaults to ['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION']. See also renderRequest().
public array $displayVars = ['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION']