Update WebBrowser.xml (#7993)

Author: merriemcgaw

xml/System.Windows.Forms/WebBrowser.xml

@@ -90,7 +90,8 @@
 > [!NOTE]
 >  The <xref:System.Windows.Forms.WebBrowser> class can only be used in threads set to single thread apartment (STA) mode. To use this class, ensure that your `Main` method is marked with the <xref:System.STAThreadAttribute> attribute.  
   
-   
+> [!NOTE]
+> For accessibility purposes the <xref:System.Windows.Forms.Control.TabStop> property should be set to `false` when there is no content to display in the <xref:System.Windows.Forms.WebBrowser> control. Change the value to `true` to enable users to navigate via keyboard into the contents of the control.
   
 ## Examples  
  The following code example demonstrates how to implement an address bar for use with the <xref:System.Windows.Forms.WebBrowser> control. This example requires that you have a form that contains a <xref:System.Windows.Forms.WebBrowser> control called `webBrowser1`, a <xref:System.Windows.Forms.TextBox> control called `TextBoxAddress`, and a <xref:System.Windows.Forms.Button> control called `ButtonGo`. When you type a URL into the text box and press ENTER or click the **Go** button, the <xref:System.Windows.Forms.WebBrowser> control navigates to the URL specified. When you navigate by clicking a hyperlink, the text box automatically updates to display the current URL.