Clarify nesting of config switch

docs/core/compatibility/core-libraries/6.0/system-drawing-common-windows-only.md

@@ -46,19 +46,20 @@ Because `System.Drawing.Common` was designed to be a thin wrapper over Windows t
 
 `libgdiplus` is the main provider of the cross-platform implementation of `System.Drawing.Common` on the native side. `libgdiplus` is effectively a reimplementation of the parts of Windows that `System.Drawing.Common` depends on. That implementation makes `libgdiplus` a non-trivial component. It's around 30,000 lines of C code that's largely untested, and it lacks a lot of functionality. `libgdiplus` also has numerous external dependencies for image processing and text rendering, such as `cairo`, `pango`, and other native libraries. Those dependencies make maintaining and shipping the component even more challenging. Since the inclusion of the Mono cross-platform implementation, we have redirected numerous issues to `libgdiplus` that never got fixed. In comparison, other external dependencies we have taken, such as `icu` or `openssl`, are high-quality libraries. It's not viable to get `libgdiplus` to the point where its feature set and quality is on par with the rest of the .NET stack.
 
-From analysis of NuGet packages, we've observed that `System.Drawing.Common` is used cross-platform mostly for image manipulation, such as QR code generators and text rendering. We haven't noticed heavy graphics usage, as our cross-platform graphics support is incomplete. The usages we see of `System.Drawing.Common` in non-Windows environments are typically well supported with SkiaSharp and ImageSharp.
+From analysis of NuGet packages, we've observed that `System.Drawing.Common` is used cross-platform mostly for image manipulation, such as QR code generators and text rendering. We haven't noticed heavy graphics usage, as our cross-platform graphics support is incomplete. The usages we see of `System.Drawing.Common` in non-Windows environments are typically well supported with SkiaSharp.
 
 `System.Drawing.Common` will continue to evolve only in the context of Windows Forms and GDI+.
 
 ## Recommended action
 
 To use these APIs for cross-platform apps, migrate to one of the following libraries:
 
-- [ImageSharp](https://github.com/SixLabors/ImageSharp)
 - [SkiaSharp](https://github.com/mono/SkiaSharp)
 - [Microsoft.Maui.Graphics](https://github.com/dotnet/Microsoft.Maui.Graphics)
 
-Alternatively, you can enable support for non-Windows platforms in .NET 6 by setting the `System.Drawing.EnableUnixSupport` [runtime configuration switch](../../../runtime-config/index.md) to `true` in the *runtimeconfig.json* file:
+Alternatively, you can enable support for non-Windows platforms in .NET 6 by setting the `System.Drawing.EnableUnixSupport` [runtime configuration switch](../../../runtime-config/index.md) to `true` in the *runtimeconfig.json* file.
+
+*runtimeconfig.template.json* template file:
 
 ```json
 {
@@ -68,7 +69,22 @@ Alternatively, you can enable support for non-Windows platforms in .NET 6 by set
 }
 ```
 
-This configuration switch was added to give cross-platform apps that depend heavily on this package time to migrate to more modern libraries. However, non-Windows bugs will not be fixed. In addition, this switch has been removed in .NET 7.
+*[appname].runtimeconfig.json* output file:
+
+```json
+{
+   "runtimeOptions": {
+      "configProperties": {
+         "System.Drawing.EnableUnixSupport": true
+      }
+   }
+}
+```
+
+> [!NOTE]
+>
+> - This configuration switch was added to give cross-platform apps that depend heavily on this package time to migrate to more modern libraries. However, non-Windows bugs will not be fixed.
+> - This switch is only available in .NET 6.
 
 ## Affected APIs