Bug Custom Input Processor cannot serialize String value

I am trying to write a custom processor for a mouse & keyboard-only control scheme for my 2D game. I'm planning to use this custom processor in a 'Look' input value that points in the direction the player wants to look towards, this is simple for a gamepad-only control scheme (just the joystick value). However, I want the player to have to move their mouse to look around - therefore I thought a custom processor for this mouse & keyboard-only control scheme would be ideal. But it seems that Unity is unable to serialize my String value for this custom processor.

I followed this article on the documentation: https://docs.unity3d.com/Packages/com.unity.inputsystem@1.0/manual/Processors.html

Code (CSharp):

1.  
2. using System;
3. using UnityEditor;
4. using UnityEngine;
5. using UnityEngine.InputSystem;
6.  
7. #if UNITY_EDITOR
8. [InitializeOnLoad]
9. #endif
10. public class PointTowardsCursorInputProcessor  : InputProcessor<Vector2> {
11. [Tooltip("Target GameObject with this tag")]
12. public String Tag = "Player";
13.  
14. #if UNITY_EDITOR
15. static PointTowardsCursorInputProcessor () {
16.   Initialize();
17. }
18. #endif
19.  
20. [RuntimeInitializeOnLoadMethod]
21. static void Initialize() {
22.   InputSystem.RegisterProcessor<PointTowardsCursorInputProcessor >();
23. }
24.  
25. public override Vector2 Process(Vector2 value, InputControl control) {
26.   return value;
27. }
28. }
29.  

Error code:


Version info:
InputSystem version: 1.4.4
Unity version: 2021.3.16f1[/B]

 

String parameters are not currently supported.