PowerPoint: Deleting slide from Thumbnails pane breaks access until refocused #3415

ERROR - scriptHandler.executeScript (20:17:36):
error executing script: <bound method Dynamic_DocumentWindowContentGenericClientIAccessibleWindowNVDAObject.script_selectionChange of <NVDAObjects.Dynamic_DocumentWindowContentGenericClientIAccessibleWindowNVDAObject object at 0x059C6AD0>> with gesture u'down arrow'
Traceback (most recent call last):
  File "scriptHandler.py", line 165, in executeScript
    script(gesture)
  File "appModules\powerpnt.py", line 438, in script_selectionChange
    self.handleSelectionChange()
  File "appModules\powerpnt.py", line 422, in handleSelectionChange
    if obj and obj!=eventHandler.lastQueuedFocusObject:
  File "NVDAObjects\__init__.py", line 302, in __ne__
    return not self.__eq__(other)
  File "NVDAObjects\__init__.py", line 297, in __eq__
    return self._isEqual(other)
  File "appModules\powerpnt.py", line 492, in _isEqual
    return super(SlideBase,self)._isEqual(other) and self.name==other.name
  File "baseObject.py", line 34, in __get__
    return instance._getPropertyViaCache(self.fget)
  File "baseObject.py", line 110, in _getPropertyViaCache
    val=getterMethod(self)
  File "appModules\powerpnt.py", line 504, in _get_name
    number=self.ppObject.slideNumber
  File "comtypesMonkeyPatches.py", line 32, in new__getattr__
    return old__getattr__(self,name)
  File "C:\Program Files (x86)\Python27\lib\site-packages\comtypes\client\lazybind.py", line 149, in __getattr__
    return self._comobj._invoke(descr.memid, descr.invkind, 0)
  File "C:\Program Files (x86)\Python27\lib\site-packages\comtypes\automation.py", line 664, in _invoke
    dp, var, None, argerr)
COMError: (-2147352567, 'Exception occurred.', (u'Slide.SlideNumber : Object does not exist.', u'Microsoft Office PowerPoint 2007', u'', 0, None))