It’s not always that you want your Silverlight application to have a background color. Instead you can use the color from the hosting HTML page – and it’s easy!
In your HTML that hosts the Silverlight object add these parameters and you’re done:
<param name="background" value="transparent" /> <param name="windowless" value="true" />
by xamlgeek
These settings will hurt performance.
Windowless mode is computationally expensive, especially in combination with a transparent plug-in background.
See the Silverlight blog:
http://blogs.msdn.com/silverlight_sdk/archive/2008/11/12/limitations-of-windowless-mode-for-silverlight.aspx
I agree – sometimes it’s just necessary though and depending on the project it can be acceptable.