title: Strange "go to sources" behaviour in VS
body: <p><img src="https://i.stack.imgur.com/Kx69z.png" alt="alt text"></p>
  
  <p>This is what I get when I select "go to definition" in the ConfigTests.cs. But I expected to go to already opened Config.cs with actual declaration.<br>
  What did I do wrong?</p>