New macOS Lunacy 8 app crashes when choosing Lunacy -> About Avalonia in menu

Deadpikle

Howdy,

On macOS Big Sur, every time I click the menu bar Lunacy text, then click "About Avalonia", the app crashes.

Me thinks maybe your Avalonia native menu isn't set up properly? You can put something like the following in your App.xaml in the Application tag to control what goes under the Lunacy title in your native menu:

```xml

<NativeMenu.Menu>

   <NativeMenu>

     <NativeMenuItem Header="About Lunacy"

                     Clicked="AboutItem_Clicked" />

     <NativeMenuItem Header="Check for Updates..."

                     Clicked="CheckForUpdatesItem_Clicked" />

   </NativeMenu>

 </NativeMenu.Menu>

```

Alex

Hi!

Thank you for the report. We'll fix this issue ASAP.