FPS Walker bunny hops if stop walking while on slopes

Surprised not to see a peep nor word about this issue as it's inherent in all the rigidbody FPS scripts that disable gravity i.e. FPSwalker scripts.

My code is specifically using GravityFPSWalker.

When walking up any slope (the more angle the more it happens), if a player stops input, the gameobject will hop. I assume this is an effect of an object colliding into an angle this steep (Like real physics would treat a capsule colliding at this angle) but it kinda ruins the otherwise awesome motion of this script. moving on slopes is very common in my game and not hopping when stopping on slopes is important to me. Any way anyone can see to solve this issue?

 using UnityEngine;
 
 /* -------------------------------------------------------------------------------
 GravityFPSWalker
 
 This component is added to a GameObject with a RigidBody. It allows the player
 to move the RigidBody using the vertical and horizontal inputs, and to jump
 using the jump button.
 
 The RigidBody is pushed towards its own custom Gravity vector. The body will
 rotate to stay upright with the RotationRate.
 
 This component uses a raycast to determine if the RigidBody is standing on 
 the ground. The GroundHeight variable should be the distance between the
 GameObject transform and a little further than the bottom of the RigidBody.
 
 The LookTransform should be a child GameObject which points in the direction
 that the player is looking at. This could for example be a child GameObject 
 with a camera. The LookTransform is used to determine the movement veectors.
 ------------------------------------------------------------------------------ */
 [RequireComponent(typeof(Rigidbody))]
 public class GravityFPSWalker : MonoBehaviour {
 
 public Transform LookTransform;
 public Vector3 Gravity = Vector3.down * 9.81f;
 public float RotationRate = 0.1f;
 public float Velocity = 8;
 public float GroundControl = 1.0f;
 public float AirControl = 0.2f;
 public float JumpVelocity = 5;
 public float GroundHeight = 1.1f;
 private bool jump;
 
 void Start() { 
     rigidbody.freezeRotation = true;
     rigidbody.useGravity = false;
 }
 
 void Update() {
     jump = jump || Input.GetButtonDown("Jump");
 }
 
 void FixedUpdate() {
     // Cast a ray towards the ground to see if the Walker is grounded
     bool grounded = Physics.Raycast(transform.position, Gravity.normalized, GroundHeight);
 
     // Rotate the body to stay upright
     Vector3 gravityForward = Vector3.Cross(Gravity, transform.right);
     Quaternion targetRotation = Quaternion.LookRotation(gravityForward, -Gravity);
     rigidbody.rotation = Quaternion.Lerp(rigidbody.rotation, targetRotation, RotationRate);
 
     // Add velocity change for movement on the local horizontal plane
     Vector3 forward = Vector3.Cross(transform.up, -LookTransform.right).normalized;
     Vector3 right = Vector3.Cross(transform.up, LookTransform.forward).normalized;
     Vector3 targetVelocity = (forward * Input.GetAxis("Vertical") + right * Input.GetAxis("Horizontal")) * Velocity;
     Vector3 localVelocity = transform.InverseTransformDirection(rigidbody.velocity);
     Vector3 velocityChange = transform.InverseTransformDirection(targetVelocity) - localVelocity;
 
     // The velocity change is clamped to the control velocity
     // The vertical component is either removed or set to result in the absolute jump velocity
     velocityChange = Vector3.ClampMagnitude(velocityChange, grounded ? GroundControl : AirControl);
     velocityChange.y = jump && grounded ? -localVelocity.y + JumpVelocity : 0;
     velocityChange = transform.TransformDirection(velocityChange);
     rigidbody.AddForce(velocityChange, ForceMode.VelocityChange);
 
     // Add gravity
     rigidbody.AddForce(Gravity * rigidbody.mass);
 
     jump = false;
 }
 
 }