Add Blazor VS debugging troubleshoot entry (#18959)

Author: guardrex

aspnetcore/blazor/debug.md

@@ -5,7 +5,7 @@ description: Learn how to debug Blazor apps.
 monikerRange: '>= aspnetcore-3.1'
 ms.author: riande
 ms.custom: mvc
-ms.date: 05/31/2020
+ms.date: 06/25/2020
 no-loc: [Blazor, "Identity", "Let's Encrypt", Razor, SignalR]
 uid: blazor/debug
 ---
@@ -225,3 +225,4 @@ If you're running into errors, the following tips may help:
 
 * In the **Debugger** tab, open the developer tools in your browser. In the console, execute `localStorage.clear()` to remove any breakpoints.
 * Confirm that you've installed and trusted the ASP.NET Core HTTPS development certificate. For more information, see <xref:security/enforcing-ssl#troubleshoot-certificate-problems>.
+* Visual Studio requires the **Enable JavaScript debugging for ASP.NET (Chrome, Edge and IE)** option in **Tools** > **Options** > **Debugging** > **General**. This is the default setting for Visual Studio. If debugging isn't working, confirm that the option is selected.