How to change debugger settings for debugging individual unit tests from VS 2015 Test Explorer

Test Explorer allows to run tests under debugger. However debugger settings used in this case are different from that set for the test project and prevent efficient debugging. I would like to limit debugging to managed only for UWP class library while debugerr starts always in mixed native/managed mode. This prevents any debugging as .NET Core does not support mixed mode debugging. I work on VS 2015.

After checking and testing all possible settings I have failed to switch debugging mode from mixed to managed only. Any ideas?