SEBWIN-411: Fixed audio / video playback not stopping when closing additional browser window.

SafeExamBrowser.Browser/BrowserApplicationInstance.cs

@@ -109,6 +109,7 @@ namespace SafeExamBrowser.Browser
 
 		internal void Terminate()
 		{
+			control.Destroy();
 			window.Close();
 		}
 
@@ -459,6 +460,7 @@ namespace SafeExamBrowser.Browser
 		private void Window_Closing()
 		{
 			logger.Info($"Instance has terminated.");
+			control.Destroy();
 			Terminated?.Invoke(Id);
 		}
 

SafeExamBrowser.Browser/BrowserControl.cs

@@ -74,6 +74,14 @@ namespace SafeExamBrowser.Browser
 			this.requestHandler = requestHandler;
 		}
 
+		public void Destroy()
+		{
+			if (!IsDisposed)
+			{
+				Dispose(true);
+			}
+		}
+
 		public void Initialize()
 		{
 			AddressChanged += (o, args) => addressChanged?.Invoke(args.Address);

SafeExamBrowser.UserInterface.Contracts/Browser/IBrowserControl.cs

@@ -51,6 +51,11 @@ namespace SafeExamBrowser.UserInterface.Contracts.Browser
 		/// </summary>
 		event TitleChangedEventHandler TitleChanged;
 
+		/// <summary>
+		/// Finalizes the browser control (e.g. stops audio / video playback) and releases all used resources.
+		/// </summary>
+		void Destroy();
+
 		/// <summary>
 		/// Initializes the browser control.
 		/// </summary>