Inconsistent user gesture requirement for requestFullscreen()

Description
WebView2 appears to relax most user gesture requirements imposed on the web, such as allowing audio playback on startup. This is a nice feature of WebView2, especially since often these restrictions make sense on the web, but not in an app.

I've noticed the user gesture requirement for requestFullscreen() seems inconsistent. It looks like the call is still blocked if you did not yet click in the app. If you did focus the app already, the API can then be called at any time. It should be allowed at any time, even before clicking in the app, so you can get a fullscreen-on-startup experience (especially relevant to web games).

Version
SDK: 1.0.705.50
Runtime: 88.0.705.68 stable
Framework: Win32
OS: Windows 10 x64 version 20H2

Repro Steps
Demo app: requestfullscreentest.zip

1. Launch the app but don't interact with it.
2. After the splash screen has finished and a simple shooter game is running, press F12.
3. Check the browser console: a call to requestFullscreen failed with Failed to execute 'requestFullscreen' on 'Element': API can only be initiated by a user gesture.

Try again but click in the middle of the splash screen while it is showing. When the splash screen finishes, it enters fullscreen mode successfully.

Additional context
We could code the app to enter fullscreen on startup, but this is not web compatible, since the JavaScript code won't think it's in fullscreen mode. It would be best if WebView2 just allowed calls to requestFullscreen at any time.

AB#31758227

Start by running the linked requestfullscreentest.zip demo and compare requestFullscreen() before and after clicking the splash screen. Confirm the current gesture-dependent behavior and define completion as allowing the call before interaction while keeping the JavaScript fullscreen state consistent.