Comment 2 for bug 1162760

StacktraceTop:
 XGetWindowProperty (dpy=dpy@entry=0x23c67b0, w=w@entry=661, property=property@entry=304, offset=offset@entry=0, length=length@entry=9223372036854775807, delete=delete@entry=0, req_type=req_type@entry=33, actual_type=actual_type@entry=0x7fff5b5828d0, actual_format=actual_format@entry=0x7fff5b5828cc, nitems=nitems@entry=0x7fff5b5828d8, bytesafter=bytesafter@entry=0x7fff5b5828e0, prop=prop@entry=0x7fff5b5828e8) at ../../src/GetProp.c:61
 _wnck_get_window (screen=<optimized out>, xwindow=661, atom=304, val=val@entry=0x7fff5b582978) at xutils.c:143
 update_active_window (screen=0x241f4e0) at screen.c:2016
 do_update_now (screen=0x241f4e0) at screen.c:2264
 update_idle (data=<optimized out>) at screen.c:2282