I have worked on a number of projects using Selenium Java and the Firefox Web Driver, on a variety of platforms. Time and again, I come across incompatibilities between the version of the Selenium WebDriver we use and the version of Firefox installed.
The first line of defence is, of course, to make sure that we use the latest version of WebDriver and the latest version of FireFox.
Sometimes, that is not possible though, because we are using an older version of Java, or simply because the path of least resistance is to use the version of Firefox that is distributed with the OS.
I would really like to have a reliable Compatibility Matrix that tells me which version of Firefox I can use with which version of Selenium WebDriver. Where can I find one?