Found 3 packages
WeakSubscribe to events. Taken from the MvvmCross codebase and provided on its own. WeakSubscribe hands responsibility to the client code, unlike using a WeakEventManager which requires modified events. See project site for instructions.
Avoid memory leaks by using Weak Events. This package provides a Weak Event Manager to create weak events and a Weak Event Handler to weakly subscribe to standard events.
Event aggregator pattern implementation for .NET and Blazor applications. Provides publish-subscribe functionality with support for async events, weak references, and thread marshalling.