Deprecation Guide for Optional Feature: application-template-wrapper

Setting the application-template-wrapper optional feature to true has been deprecated. You must set this feature to false, disabling the application wrapper. For more details on this optional feature, including the changes in behavior disabling it causes and how you can disable it, see the optional features section of the Ember guides. You can also run npx @ember/octanify to set this feature to the correct value.