Although Internet Explorer is still the most widely used browser according to statistics available at the time this chapter is being written, Mozilla Firefox has made significant inroads and is being used by more and more people. As a result, you'll likely need to debug your ASP.NET AJAX applications in Firefox as well as Internet Explorer. Firefox doesn't offer any direct integration with Visual Studio 2008, unfortunately, but it does have extensions that can be downloaded and installed that make it rather straightforward to debug ASP.NET AJAX applications.
One of the most popular debugging extensions available for Firefox is Firebug. You can download Firebug from http://getfirebug.com. Once installed, Firebug allows you to view the Document Object Model (DOM) of a page, view CSS details, and perform various debugging operations.
You can view a page directly in Firefox from Visual Studio by right-clicking the page in the Solution Explorer and selecting Browse With from the menu. The Browse With dialog box appears. Click the Add button to view the Add Program dialog box, as shown in Figure 15-14, and locate where firefox.exe was installed on your computer. Once the program is added to the list of available browsers, you can select it and press the Browse button to view any page directly in Firefox instead of in Internet Explorer.
Once a page is loaded in Firefox, you can access Firebug functionality in several ...