Using 2 different WebView2 with the same CoreWebView2Environment

Question

I have an Excel VSTO add-in that uses WebView2 components into its panels.
WebView2 Documentation

I am trying to display two WebView2 using the same CoreWebView2Environment object, so I can set it up at launch without having to manage several folders.
At runtime, both webviews are initialized however only one shows up correctly. The other loads an incomplete version of itself without any error raised in C# or the web console.

I am creating the environment folder on add-in start-up:

public static async void CreateEnvironmentDirectory()
{
    string userDataStorage = Path.Combine(Path.GetTempPath(), MY_APP_FOLDER);
    CoreWebView2EnvironmentOptions options = new("--disk-cache-size=1 ");
    
    MyCoreWebView2Environment = await CoreWebView2Environment.CreateAsync(default, userDataStorage, options);
}

Then, when the panel is loading:

private async Task InitializeWebviews()
{
    await InitializeWebview(MyFirstWebview, myFirstUrl);
    await InitializeWebview(MySecondWebview, mySecondUrl);
}
private async Task InitializeWebview(WebView2 webview, string url)
{
    await webview.EnsureCoreWebView2Async(WebView2Manager.MyCoreWebView2Environment);
    webview.Navigate(url);
}

After tweaking around for a bit I discovered I could make it work by throwing a Thread.Sleep(500) in between both initialisations. It works on debug build only though.
For obvious reasons this is not the kind of solution I'm looking for, and I'm out of clean ideas to have it run properly.

Any help would be appreciated.