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Created attachment 9878 [details]
When using the Unified API, extensions methods are not recognized unless qualified with the "this" keyword.
**Steps to Reproduce:**
1. Try to build the attached TextTest project (Unified API app)
The extension method EndEditing for UITextField is not recognized. See screenshot:http://screencast.com/t/zBGApahG
The method should be recognized and not require the "this" keyword.
**Build Date & Platform:**
There is a Classic API project in the solution to show this is not an issue when using the Classic API.
Workaround: use the "this" keyword
This is just how C# works, extension methods can only be invoked using an instance expression (the implicit 'this' inside instance methods is not enough) 
This is a deliberate API difference between Classic and Unified.