Changes needed in python xlib to support UTF8 WM_NAME

python-xlib_utf_name_support.diff

Index: Xlib/Xatom.py
===================================================================
--- Xlib/Xatom.py       (revision 171)
+++ Xlib/Xatom.py       (working copy)
@@ -85,3 +85,6 @@
 WM_CLASS = 67
 WM_TRANSIENT_FOR = 68
 LAST_PREDEFINED = 68
+#Added
+UTF8_STRING = 291
+COMPOUND_TEXT = 446
Index: Xlib/xobject/drawable.py
===================================================================
--- Xlib/xobject/drawable.py    (revision 171)
+++ Xlib/xobject/drawable.py    (working copy)
@@ -640,10 +640,15 @@
                              onerror = onerror)

     def get_wm_name(self):
-        d = self.get_full_property(Xatom.WM_NAME, Xatom.STRING)
+        d = self.get_full_property(Xatom.WM_NAME, 0)
         if d is None or d.format != 8:
             return None
         else:
+            if d.property_type == Xatom.UTF8_STRING:
+                #print "UTF:", type(d.value), repr(d.value)
+                return d.value.decode("utf-8")
+            elif d.property_type == Xatom.COMPOUND_TEXT:
+                return d.value.decode("utf-8", errors='ignore') 
             return d.value

     def set_wm_icon_name(self, name, onerror = None):

To apply this patch install python xlib: pip install svn+https://python-xlib.svn.sourceforge.net/svnroot/python-xlib/tags/xlib_0_15rc1/ and go into installed folder lib/python2.7/site-packages and patch it
patch -b -p0 -i python-xlib_utf_name_support.diff. (-b makes backup -i inputs patch file)

To use it in selfspy then you only need utf8 branch for selfspy.

It can be achieved also by changing selfspy only: selfspy/selfspy#126

The approach above would fall short for text=COMPOUND_TEXT (used by rxvt-unicode).
Using _NET_WM_NAME instead appears to be the simpler approach.