Hololens: Executing IWithMouseEvents.MouseEvent(...) releases MRTK's PointerDown.

Description

Executing IWithMouseEvents.MouseEvent(...) releases MRTK's PointerDown.

Version
SDK: com.microsoft.mixedreality.webview.unity-0.17.1-pre.3.tgz
Runtime: Unity2021.3.24 (Run on Editor)
Framework: Unity2021.3.24, MRTK2.8.3
OS: Windows10 22H2

Regression
Was this working before but has regressed? > No.
If yes, what version did this last work on?

Repro Steps

1. Clone this repository.
   https://github.com/MicrosoftEdge/WebView2Samples/
2. Open this sample in UnityEditor.
   https://github.com/MicrosoftEdge/WebView2Samples/tree/main/GettingStartedGuides/HoloLens2_GettingStarted/HoloLens2GetStartedApp
3. Attach this script to "Canvas"

using Microsoft.MixedReality.Toolkit.Input;
using Microsoft.MixedReality.WebView;
using UnityEngine;

public class Sample : MonoBehaviour, IMixedRealityPointerHandler
{
    private IWebView webView;

    private void Start()
    {
        GetComponentInChildren<WebView>().GetWebViewWhenReady((IWebView webView) =>
        {
            this.webView = webView;
        });
    }

    public void OnPointerDown(MixedRealityPointerEventData eventData)
    {
        Debug.Log("OnPointerDown");

        WebViewMouseEventData mouseEvent = new WebViewMouseEventData
        {
            X = 0,
            Y = 0,
            Type = WebViewMouseEventData.EventType.MouseDown,
            Button = WebViewMouseEventData.MouseButton.ButtonLeft,
            TertiaryAxisDeviceType = WebViewMouseEventData.TertiaryAxisDevice.PointingDevice
        };

        (webView as IWithMouseEvents).MouseEvent(mouseEvent);
    }

    public void OnPointerDragged(MixedRealityPointerEventData eventData)
    {
        Debug.Log("Dragged");
    }

    public void OnPointerUp(MixedRealityPointerEventData eventData)
    {
        Debug.Log("OnPointerUp");
    }

    public void OnPointerClicked(MixedRealityPointerEventData eventData)
    {
        
    }
}

4. Run it, put the pointer on the Canvas and press the left mouse button.
5. The following is logged to the console:

OnPointerDown
Dragged
OnPointerUp  

I expect only PointerDown (and Dragged) to be logged.
Commenting out this line gives the expected behavior.

(webView as IWithMouseEvents).MouseEvent(mouseEvent);

Screenshots

Additional context

AB#45473968