Failed to marshal the Objective-C object

[scarabdesign]

Visual Studio Enterprise 2019 for Windows
C# 9.0
Xamarin iOS 15.0.0.8
Windows 10 / macOS 11.6
iPhone with iOS 15 (a few different models)

My iOS app is returning this error from time to time since iOS 15.

Failed to marshal the Objective-C object 0x283f57080 (type: Square_SocketRocket_WebSocket__WebSocketDelegate). Could not find an existing managed instance for this object, nor was it possible to create a new managed instance (because the type 'Square.SocketRocket.WebSocket+_WebSocketDelegate' does not have a constructor that takes one IntPtr argument).
Additional information:
	Selector: webSocket:didCloseWithCode:reason:wasClean:
	Method: Square.SocketRocket.WebSocket/_WebSocketDelegate:WebSocketClosed (Square.SocketRocket.WebSocket,Square.SocketRocket.StatusCode,string,bool)
  at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)
  at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) <0x1045076f0 + 0x0005f> in <e6d97443f5714185be8a5ae6def186ed#b54e071fd57ec77c1c927dfc03ab3584>:0 
  at ERPXamarin.iOS.Application.Main (System.String[] args) <0x102f89660 + 0x00023> in <f1aa27121c6a43c1b9012db9d8bcee83#b54e071fd57ec77c1c927dfc03ab3584>:0 

My app seems to catch and report the error to me (in a managed way) and recover from it by trying again, but it seems to always present the user with the option to send a bug report to Apple, which I'm not fond of.

I'm catching the error from an event listener in the AppDelegate.cs:

        public override bool FinishedLaunching(UIApplication application, NSDictionary launchOptions)
        {
            Runtime.MarshalObjectiveCException += Runtime_MarshalObjectiveCException;
            [...]
        }
            
        private void Runtime_MarshalObjectiveCException(object sender, MarshalObjectiveCExceptionEventArgs args)
        {
            args.ExceptionMode = MarshalObjectiveCExceptionMode.ThrowManagedException;
            if (args.Exception == null || args.Exception.CallStackSymbols == null) return;
            Logger.LogError("AppDelegate.Runtime_MarshalObjectiveCException: " + args.Exception.CallStackSymbols.Aggregate((s1, s2) => s1 + "\r\n" + s2));
        }