text: Title: After doing some operation, I am getting element not found error for previously accessed element. 
  Body: ## Expected Behavior
  It should found the element and continue the process.
  
  ## Actual Behavior
  its failing and showing error as "element not found"
  
  ## Steps to Reproduce the Problem
  
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  ## Short Example of Code to Demonstrate the Problem
  main_window=Application(backend="uia").connect(title_re="Editor*")
  pane= main_window.window(class_name="WindowsForms10.MDICLIENT.app.0.2bf8098_r33_ad1",control_type="Pane",top_level_only=False)
  
  Note :- getting errors as element not found for "WindowsForms10.MDICLIENT.app.0.2bf8098_r33_ad1" but the same element is displayed while running py_inspect.py
  
  ## Specifications
  
    - Pywinauto version: 0.6.8
    - Python version and bitness: python 3.6.8 and 64 bit
    - Platform and OS: 64 bit and windows
  