Silverlight 4: If the source url for the xap file does not end in .xap no splash screen is displayed by alunharford

If the source url for the xap file does not end in .xap no splash screen is displayed. This is particularly a problem for MVC users who use routing to locate the xap file.

The application itself works, but the default splash screen is not displayed. A custom splash screen is also not displayed.

Works:

<div id="silverlightControlHost">
        <object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
        
         <param name="source" value="/Silverlight/Client/MyApplication.xap" />
         <param name="onError" value="onSilverlightError" />
         <param name="background" value="white" />
         <param name="minRuntimeVersion" value="4.0.41108.0" />
         <param name="autoUpgrade" value="true" />
         <param name="allowHtmlPopupWindow" value="true"/>
         <a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.41108.0" style="text-decoration:none">
                 <img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/>
         </a>
        </object><iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe></div>
    </form>

Does not work:

<div id="silverlightControlHost">
        <object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
        
         <param name="source" value="/Silverlight/Client/MyApplication" />
         <param name="onError" value="onSilverlightError" />
         <param name="background" value="white" />
         <param name="minRuntimeVersion" value="4.0.41108.0" />
         <param name="autoUpgrade" value="true" />
         <param name="allowHtmlPopupWindow" value="true"/>
         <a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.41108.0" style="text-decoration:none">
                 <img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/>
         </a>
        </object><iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe></div>
    </form>