This issue will track the list of breaking changes that will be introduced in CoreWCF 2.X. The comments on the issue will be used to discuss the merits of these changes.

• Drop ServiceAuthorizationBehavior.AuthorizationService - Approved
• Drop DispatchRuntime.AuthorizationService - Approved
• Drop synchronous overloads from SecurityTokenAuthenticator - Approved
• Drop synchronous overloads from UserNamePasswordValidator - Approved
• Drop synchronous overloads from UserNameSecurityTokenAuthenticator - Approved
• Drop synchronous ServiceAuthenticationManager.Authenticate - Approved
• Drop synchronous overloads from ServiceAuthorizationManager - Approved
• Drop AppContext.Switch usage in favor of Runtime.IsDynamicCodeSupported in src/CoreWCF.Primitives/src/CoreWCF/Dispatcher/InvokerUtil.cs - Dependent on prior version shipping with it on by default