targetControl argument is ambiguous

The description "The automation element of interest." doesn't explain what this element is. Is it the window that is supposed to open? Is it the control that preceded the window being opened? Is the parent window, or some other ancestor element up the tree from the window being opened? How do you get his automationElement so you can register it for this method?

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#### Document Details

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* ID: 3bdd7a9a-b12c-44e7-5ed2-c1882d3a9bd6
* Version Independent ID: 6e14b54d-594d-09f2-3e4c-e976836bc0c4
* Content: [WindowPattern.WindowOpenedEvent Field (System.Windows.Automation)](https://docs.microsoft.com/en-us/dotnet/api/system.windows.automation.windowpattern.windowopenedevent?view=netframework-4.7.2)
* Content Source: [xml/System.Windows.Automation/WindowPattern.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Windows.Automation/WindowPattern.xml)
* Product: **dotnet-api**
* GitHub Login: @Xansky
* Microsoft Alias: **mhopkins**