Our application integrates with Office365 using ApplicationImpersonation.
Is ApplicationImpersonation available in Office365 GCC High? In the documentation below I read:
18 Anti-phishing for user and domain impersonation and spoof intelligence are not yet available in GCC High and DoD.
It is. If your app is using basic auth, no additional configuration is needed. If you are using Modern auth, once you register the Azure AD App you have to manually search for Exchange when adding the API permissions (select APIs my organization uses -> find and add Exchange -> add the impersonation permission).
Domain impersonation is a different thing.
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