WebBrowser control from Console app using F# - wpf

Question

I have a .netcoreapp3.1 Console App
<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>netcoreapp3.1</TargetFramework>
<UseWpf>true</UseWpf>
<UseWindowsForms>true</UseWindowsForms>
</PropertyGroup>
<ItemGroup>
<Compile Include="Program.fs" />
</ItemGroup>
</Project>
In Program.fs, I am instantiating a WebBrowser control and handling the DocumentCompleted event
let run() =
let uri = "https://www.microsoft.com"
let browser = new WebBrowser()
browser.DocumentCompleted.Add(fun _ -> handlePage browser uris)
browser.Navigate(uri)
[<STAThread>]
[<EntryPoint>]
let main argv =
run()
Console.ReadKey() |> ignore
0
When I run it, the DocumentCompleted event is never fired or handled - the program runs through to the end.
Am I missing?
Thanks in advance.

Answer 1

Am I missing?
The message pump. You need a Dispatcher to run a WPF app.
On another note, you're using the WinForms WebBrowser, that one exposes the DocumentCompleted event. The WPF variant has the LoadCompleted event, ref this post.
In WPF, however, the concept of Loaded is related to the visual tree. As you're not rendering the control, the event will never be raised. If we instead use the Navigated event, we can get there with minimal fuss.
open System
open System.Windows
open System.Windows.Controls
type BrowserApplication() =
inherit Application()
let run() =
let uri = "https://www.microsoft.com"
let browser = new WebBrowser()
browser.Navigated.Add(fun _ -> Console.WriteLine("Done navigating"))
browser.Navigate(uri)
do run();
[<EntryPoint;STAThread>]
let main argv =
BrowserApplication().Run()