Test for the WPF plug-in for Firefox

--- title: Detect Whether WPF Plug-In for Firefox Is Installed titleSuffix: "" ms.date: "03/30/2017" helpviewer_keywords: - "plug-in for Firefox [WPF]" - "detecting Firefox installation [WPF]" - "checking for the Firefox plug-in [WPF]" - "Firefox [WPF], detecting installation" - "detecting whether the WPF plug-in for Firefox is installed [WPF]" ms.assetid: 5f839373-e3fb-44f1-88ad-4a0761f02189 --- # How to: Detect Whether the WPF Plug-In for Firefox Is Installed The Windows Presentation Foundation (WPF) plug-in for Firefox enables XAML browser applications (XBAPs) and loose XAML files to run in the Mozilla Firefox browser. This topic provides a script written in HTML and JavaScript that administrators can use to determine whether the WPF plug-in for Firefox is installed. > [!NOTE] > For more information about installing, deploying, and detecting the .NET Framework, see [Install the .NET Framework for developers](/dotnet/framework/install/guide-for-developers). ## Example When the .NET Framework 3.5 is installed, the client computer is configured with a WPF plug-in for Firefox. The following example script checks for the WPF plug-in for Firefox and then displays an appropriate status message. ```html Test for the WPF plug-in for Firefox ``` If the check for the WPF plug-in for Firefox is successful, the following status message is displayed: `The WPF plug-in for Firefox is installed.` Otherwise, the following status message is displayed: `The WPF plug-in for Firefox is not installed. Please install or reinstall the .NET Framework 3.5.` ## See also - [Detect Whether the .NET Framework 3.0 Is Installed](how-to-detect-whether-the-net-framework-3-0-is-installed.md) - [Detect Whether the .NET Framework 3.5 Is Installed](how-to-detect-whether-the-net-framework-3-5-is-installed.md) - [WPF XAML Browser Applications Overview](wpf-xaml-browser-applications-overview.md)