When I attempt to use this extension using Firefox as the browser, an instance of Firefox shows pops up, hangs around for a while showing no activity, then I get an 'Exception Breakpoint' from Firefox and that's all she wrote. I have never had much luck with CSJ but this is a new low :(. Is there an update / fix for this condition, or a better Ajax crawler (preferably with Burp)? Thanks!
I am on Windows 8.1 64-bit, FF 51.0.1 (32-bit), Burp Professional 1.7.17, and Burp CSJ 1.2.
I tested with Firefox and had the same problem, but using Chromedriver from https://sites.google.com/a/chromium.org/chromedriver/downloads on Linux/64 seems to work. I’ve logged an issue on their github account which you may wish to track: https://github.com/malerisch/burp-csj/issues/9