The WPF plug-in for Firefox enables XBAPs and loose XAML files to be navigated to and run at the top-level or in an HTML IFRAME in the Firefox browser. An XBAP is a WPF application that can be published to a Web server and launched within supported browsers. Loose XAML is a XAML-only file that can be navigated to and displayed in supported browsers, much like an XML file.

<u>Microsoft DRM</u><br> It's very unlikely that you need it. It depends on the [http://plugindoc.mozdev.org/windows-all.html#WMP Windows Media Player plug-in], which is unmaintained and won't even install properly (though on Windows XP you'll find an old version is already installed). Most sites nowadays use either Flash Player ("Shockwave Flash") or HTML5 video and audio (support is built-in). A much smaller number use Silverlight. <u>Windows Presentation Foundation</u><br> It's very unlikely that you need it, unless you come across site that specifically tells you that you do. <pre>The WPF plug-in for Firefox enables XBAPs and loose XAML files to be navigated to and run at the top-level or in an HTML IFRAME in the Firefox browser. An XBAP is a WPF application that can be published to a Web server and launched within supported browsers. Loose XAML is a XAML-only file that can be navigated to and displayed in supported browsers, much like an XML file.</pre> * [http://msdn.microsoft.com/en-us/library/cc716877%28v=vs.110%29.aspx Firefox Add-ons to Support .NET Application Deployment | MSDN] * [http://www.computerworld.com/s/article/9139459/Sneaky_Microsoft_plug_in_puts_Firefox_users_at_risk Sneaky Microsoft plug-in puts Firefox users at risk | Computerworld] ---- If you're referring to [https://www.mozilla.org/en-US/plugincheck/ the Plugin Check page], you can report problems with it by [https://bugzilla.mozilla.org/enter_bug.cgi?product=Websites filing a bug report]. Classification: Other; Product: Websites; Component: plugins.mozilla.org. However, bug reports for the issues you describe already exist: * [https://bugzilla.mozilla.org/show_bug.cgi?id=579282 Bug 579282] - Plugin Check doesn't recognize Windows Presentation Foundation (WPF) plugin * [https://bugzilla.mozilla.org/show_bug.cgi?id=584824 Bug 584824] - Unable to update Microsoft DRM plugin The latter of the two bugs is marked as RESOLVED FIXED, so if you're getting an unknown plugin notice, post a comment on that bug report saying so. ---- On a related note, you have three different versions of Flash Player installed. You should perform a clean installation as follows: # From the following page, save the uninstaller somewhere handy, like the desktop. #* [http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html#main_Download_the_Adobe_Flash_Player_uninstaller Uninstall Flash Player for Windows | Adobe Support] # From the following page, save the installer for other browsers. If you also use Flash Player in Internet Explorer, also save the ActiveX version. #* [http://helpx.adobe.com/flash-player/kb/installation-problems-flash-player-windows.html#main-pars_text_4 Direct downloads of Flash Player for Windows | Adobe Support] # Exit all applications. # Run the uninstaller. # In Windows Explorer, try to open the following folders. If they still exist, delete them manually. #* <pre>C:\Windows\system32\Macromed\Flash\</pre> #* <pre>C:\Windows\SysWOW64\Macromed\Flash\</pre> #* <pre>%AppData%\Adobe\Flash Player\</pre> #* <pre>%AppData%\Macromedia\Flash Player\</pre> # Restart your computer. # Run the installer for other browsers. # Run the ActiveX installer if you downloaded it.

Also note that the Modified Preferences section in the System Details List shows a lot of preferences from older Firefox versions, so you can consider to delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release. You can use this button to go to the currently used Firefox profile folder: *Help > Troubleshooting Information > Profile Director: Show Folder (Linux: Open Director; Mac: Show in Finder) *http://kb.mozillazine.org/Profile_folder_-_Firefox