It is recommended that content being added to a map through the Unity mapping or Web Client mapping interface matches the configuration of your system (i.e., if your Integration for Esri solution is configured to use secure communication over HTTPS, you should only add content that is also configured to use HTTPS). If added content does not match the configuration of your system, mixed content issues can occur in the Web Client mapping interface.
It is recommended to configure your solution to use HTTPS and only add HTTPS content to your maps to mitigate these issues.