MusicKit JS Native WebView Authorization Flow Not Initiating

The MusicKit JS V3 documentation has this article about Native WebViews.

For some reason, my app fails to do anything after musicKitInstance.authorize() is called. I think that it is not being recognized as a WebView and is trying to open the window as if it was running in a browser, but since it's not a browser, there's no way for it to open a browser window.

Is there something I can do to make this work? I have tried many things, including setting the user agent to a few different ones for web views and seeing if it behaves differently but didn't see any different behavior.

Is there something musickit.js checks for, when determining if it's running in a WebView, that I can leverage to ensure the Native WebView workflow is followed?