It used to work after following this tutorial: http://www.sitepoint.com/debugging-xdebug-sublime-text-3/
Now, it is not working if I put a break point. However, as I found here, it does work if I add the following line of code:
xdebug_break();
I'm on Ubuntu 14.04 LTS. I think it stopped working after I hibernated the system without stopping the XDebug session. I have rebooted the system. What could happen?