Merge pull request #113490 from mrbullwinkle/mrb_04_30_2020_appservice

update to clarify github issue

Author: PRMerger9

articles/azure-monitor/app/azure-web-apps.md

@@ -3,7 +3,6 @@ title: Monitor Azure app services performance | Microsoft Docs
 description: Application performance monitoring for Azure app services. Chart load and response time, dependency information, and set alerts on performance.
 ms.topic: conceptual
 ms.date: 12/11/2019
-ms.custom: fasttrack-edit
 ---
 
 # Monitor Azure App Service performance
@@ -394,7 +393,11 @@ For the latest information on the Application Insights agent/extension, check ou
 
 ### PHP and WordPress are not supported
 
-PHP and WordPress sites are not supported. There is currently no officially supported SDK/agent for server-side monitoring of these workloads. However, manually instrumenting client-side transactions on a PHP or WordPress site by adding the client-side javascript to your web pages can be accomplished by using the [JavaScript SDK](https://docs.microsoft.com/azure/azure-monitor/app/javascript). 
+PHP and WordPress sites are not supported. There is currently no officially supported SDK/agent for server-side monitoring of these workloads. However, manually instrumenting client-side transactions on a PHP or WordPress site by adding the client-side javascript to your web pages can be accomplished by using the [JavaScript SDK](https://docs.microsoft.com/azure/azure-monitor/app/javascript).
+
+### Connection string and instrumentation key
+
+When codeless monitoring is being used, only the connection string is required. However, we still recommend setting the instrumentation key to preserve backwards compatibility with older versions of the SDK when manual instrumentation is being performed.
 
 ## Next steps
 * [Run the profiler on your live app](../app/profiler.md).