This payload defines domains that are under an enterprise’s management.
Unmarked Email Domains
Any email address that does not have a suffix that matches one of the unmarked email domains specified by the key EmailDomains will be considered out-of-domain and will be highlighted as such in the Mail app.
Managed Safari Web Domains
Opening a document originating from a managed Safari web domain causes iOS to treat the document as managed for the purpose of Managed Open In.