While developing WPF applications, you will notice a lot of binding errors being displayed in output window. I also faced this problem and tried a lot of things to get to the root cause of the problem. It was very frustrating as AncestorLevel is not used anywhere in code! and I was not able to find the place in code which is responsible for these errors.
Even after searching the various forums and articles there was no solution for this problem; but this was a very common issue and cause of this problem mentioned here, here and here is:
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