Traceback (most recent call last):
  File "/usr/share/software-center/softwarecenter/view/widgets/mkit.py", line 1117, in _on_enter
    self._colorise_label_normal()
  File "/usr/share/software-center/softwarecenter/view/widgets/mkit.py", line 1215, in _colorise_label_normal
    attrs.change(attr)
AttributeError: 'NoneType' object has no attribute 'change'