The Recorder uses Firefox as the browser to record Desktop Browser scripts, so that any events or locators captured are based on the web page as it would appear in a Firefox browser.
The Recorder includes its own version of Firefox for recording. It is not dependent on Firefox being installed on the computer to record the script, and modifying an installed copy of the Firefox browser does not affect the Recorder.
There is, however, a dependency for Flash and Silverlight plug-in support. Plug-ins are not installed on the individual browsers. For Flash, it exists as either an Internet Explorer (IE) ActiveX plug-in or as a plug-in that applies to all other browsers. To record websites that use Flash or Silverlight, your system must have these plug-ins installed appropriately for all of the playback browsers you intend to use.
Some applications may not display the same way in Firefox as they would in Internet Explorer; in some cases, some applications may not even work in the Firefox browser. Differences in the page rendering or the Document Object Module (DOM) can easily be fixed by modifying or adding an element locator. If the page does not work at all in Firefox, you can build the script manually or use custom headers to trick the host into thinking that another browser is making the request at recording time.
Each step created in the Recorder consists of user interactions abstracted into predefined actions that each browser agent interprets in its own way. This makes it possible for the Recorder to create a single script that can be run by different browser agents
For a detailed procedure for recording a script to test websites in desktop browsers, see Creating browser scripts.