[ https://issues.jboss.org/browse/WFLY-2691?page=com.atlassian.jira.plugin.... ] Stuart Douglas commented on WFLY-2691: -------------------------------------- This is because of the way Undertow's development mode works. If you are running the server on localhost and there are no headers that indicate the request has come via a proxy then by default Undertow will display stack traces rather than the error page, as it assumes that the server is being used by a developer. You can change this behaviour my modifying the 'stack-trace-on-error' attribute in the <servlet-container> element in the Undertow subsystem from 'local-only' to 'none'. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira