On a previous article, we looked at how we can change the default browser that we use to run our Silverlight application in Visual Studio.
You can definitely choose Firefox as your default browser, however, you need to be aware that if you close the tab or the browser while your Silverlight application is running, your debugging session will not end. The same applies to when you end your debugging sessions from Visual Studio – you will see that the tab or the browser does not close. You do get this behavior for free in Internet Explorer.
But the biggest difference between debugging a Silverlight application in Firefox and Internet Explorer is the cache. With Firefox, sooner or later you will see that the browser will not be loading the latest build every time you run your app. Firefox keeps feeding you the cached version. Of course, you can put a version number to you xap files but as you can imagine this gets very inefficient when you are developing a Silverlight application.
There is a plug-in in Firefox, called Web Developer (http://chrispederick.com/work/web-developer/). After installing this plug in, just disable the cache by right clicking on a web page and choosing Disable >> Cache from the menu and you should be good to go.
Another option you have is getting Firefox in Private Browsing mode. This mode, does not record anything about your session, so it should load the latest build of your Silverlight application. You can start a private session from Tools >> Start Private Session.
Internet Explorer, however, does not seem to have this problem.