diff --git a/desktop/__init__.py b/desktop/__init__.py
index d8bfcc8..40fcf1d 100644
--- a/desktop/__init__.py
+++ b/desktop/__init__.py
@@ -135,7 +135,7 @@ def _is_xfce():
     # XFCE detection involves testing the output of a program.
 
     try:
-        return _readfrom(_get_x11_vars() + "xprop -root _DT_SAVE_MODE", shell=1).strip().endswith(' = "xfce4"')
+        return _readfrom(_get_x11_vars() + "xprop -root _DT_SAVE_MODE", shell=1).strip().endswith(str.encode(' = "xfce4"'))
     except OSError:
         return 0