Documentation not sufficient for any Xamarin.Forms CustomRenderer Migration in .NET MAUI

The described code in "[Reuse custom renderers in .NET MAUI](https://learn.microsoft.com/en-us/dotnet/maui/migration/custom-renderers)" is only valid for the[ referenced example](https://learn.microsoft.com/en-us/samples/dotnet/maui-samples/custom-renderers/), but not for any custom renderer.

I tried to migrate an `Entry `CustomRenderer and got an InvalidCastException

with the code provided from the docs in the `MauiProgram.cs`

Workaround: When I add` .UseMauiCompatibility() ` to the `MauiAppBuilder `and call the `.AddCompatibilityRenderer` like:

```
var builder = MauiApp.CreateBuilder();
builder
.UseMauiCompatibility()
.UseMauiCommunityToolkit()
.UseMauiApp(serviceProvider => new App(serviceProvider))
.ConfigureFonts(fonts =>
{
fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular");
fonts.AddFont("OpenSans-Semibold.ttf", "OpenSansSemibold");
})
.ConfigureMauiHandlers((mauiHandlerCollection) =>
{
#if ANDROID
mauiHandlerCollection.AddCompatibilityRenderer(
typeof(MyEntry),
typeof(TaskyApp.Droid.CustomRenderer.MyEntryRenderer));
#elif IOS
mauiHandlerCollection.AddCompatibilityRenderer(
typeof(MyEntry),
typeof(TaskyApp.iOS.CustomRenderer.MyEntryRenderer));
#endif
});
```

it works.

Code example is provided [here](https://github.com/ericbrunner/TaskyApp.Maui.SingleProject/commit/7fb03696f511b90a725ad9c943c1c8d248ab7726).

It would be good when the docs get updated to capture any custom renderer reuse.

---
#### Document Details

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* ID: c787fde2-1c9c-62d4-2cdd-93681e0c1ff5
* Version Independent ID: c787fde2-1c9c-62d4-2cdd-93681e0c1ff5
* Content: [Reuse custom renderers in .NET MAUI - .NET MAUI](https://learn.microsoft.com/en-us/dotnet/maui/migration/custom-renderers)
* Content Source: [docs/migration/custom-renderers.md](https://github.com/dotnet/docs-maui/blob/main/docs/migration/custom-renderers.md)
* Product: **dotnet-mobile**
* Technology: **dotnet-maui**
* GitHub Login: @davidbritch
* Microsoft Alias: **dabritch**