A couple of years ago, I designed a bunch of automatic tests for a webapplication using Molybdenum. Some of these checked the data showed in a rss feed through an xml parser. The test required the browser to show the rss as a simple xml file.
At that time I managed to turn off firefox built-in rss reader changing a parameter in the feedconverter.js file. With the major updates in Firefox (4.0 to now) this file is missing and the developers seems to have left no room for this kind of trick.
Do you know a native way to turn off the built-in rss reader?
P.S. = Solutions using the view-source: URL suffix does not work in this case, because the open command answers Failure: Access to restricted URI denied