Explicitate the domain of virtual-keys must always be used for accelerators.

Author: rubens-msft

hub/apps/design/input/keyboard-accelerators.md

@@ -586,6 +586,9 @@ We recommend localizing all keyboard accelerators. You can do this with the stan
 </Button>
 ```
 
+> [!NOTE]
+> Keyboard accelerators are implemented as virtual-keys. Localized accelerators must be chosen from the predefined domain of virtual-keys (see [Virtual-Key codes](/windows/win32/inputdev/virtual-key-codes)). Any other character is not supported and will lead to Xaml parser error.
+
 ### Setup an accelerator programmatically
 
 Here is an example of programmatically defining an accelerator: