Trouble with Sample Scene

Hello, I am trying to get the sample scene working in the Unity 2019.4.11f1 editor and it is unable to produce a webpage.

I originally was setting my platform to WebGL, and I have followed the instructions to copy over and set the "Resolution and Presentation" settings to the unity-webview version.

When I click play, the sample text animation plays and nothing happens. I have tried multiple URLs. I have also made a unity build a few times and launched the webpage to be greeted with this error:

An error occurred running the Unity content on this page. See your browser JavaScript console for more info. The error was: ReferenceError: UnityProgress is not defined

Afterwards, I switched over to the Android platform, and tried running that in-editor, and in the console log it says: "Webview is not supported on this platform."

Also, as a side note, I originally imported the package as by adding the dependency to my package manifest.json file, and upon doing so, it seems that the "SampleWebView.cs" script is not included. I think that this would be helpful to include in the package as I was a little confused when trying to run the scene initially.

Do you have any idea what I could be doing wrong? I am running on a Windows machine, which I know is not supported, so I need to build out using either the Android or WebGL versions. Ideally, I will be creating an app that launches on both these platforms.

Start by reproducing the sample scene with Unity 2019.4.11f1 on the WebGL and Android platforms, checking the browser JavaScript console and the Android console output. Inspect the package manifest.json and the reported SampleWebView.cs omission. Done means the supported sample workflow is documented or corrected, with the UnityProgress and platform-support behavior explained.