title: Activate auto-complete for C# in Visual Studio 2019
body: <p>I have the problem, that I get some suggestions for autocompletion
  (for example, I type "Cons" and I get the suggestion for "Console"), but these can't be applied with the Return-key.</p>
  
  <p>Normally, the suggestion is fully blue, and gets attached, when I press 'enter', but for some time now, the suggestion has a blue border and pressing 'enter' results in a new line.
  Where can I change these settings, so IntelliSense completes the words again, while I write them?
  I already tried the IntelliSense-Settings in the C#-options, but these settings didn't change anything</p>