I already follow this topic 

https://www.outsystems.com/forums/discussion/49509/apple-app-transport-security-ats/
and do some configuration at Extensibility Configurations follow this document
https://success.outsystems.com/documentation/10/delivering_mobile_apps/customize_your_mobile_app/configure_accessible_domains_for_your_mobile_app/
but the 

NSAllowsArbitraryLoads = True always, can some body help?