Description of problem:
In the XFCE DE, when setting the default web browser to Firefox, opening a URL in another program (or via xdg-open) yields a new firefox window to the home page. 

Version-Release number of selected component (if applicable):
0.10.2-8.fc21

How reproducible:
100%

Steps to Reproduce:
1. set firefox to the default browser in XFCE's preferred applications settings dialog
2. run xdg-open http://fedoraproject.org/

Actual results:
A new firefox window opens to the home page

Expected results:
a new tab/window loading the specified url instead.

Additional info:
This is apparently due to an OLD workaround in the EXO package that is no longer needed on current firefox versions.

https://support.mozilla.org/en-US/questions/1049337#answer-699365