title: What does the prompt "Do you want to add the following file to Git?" do exactly?
body: <p>I have been pressing "No", but GitHub Desktop still lists it as being staged and ready to be committed. My partner, him, uses the Command Prompt and not GitHub Desktop, and has been pressing "Yes" and reports the same behaviour (the file gets committed).</p>
  
  <p>So what exactly does this prompted message do ?</p>
  
  <p>NOTE: We both use IntelliJ, which is the application prompting us this message.</p>
  
  <p>EDIT: Adding the screenshot below for clarity. The green item is the result of me selecting 'YES' on the prompt, and the red item is the result of me selecting 'NO' on the prompt. We can see they both are presented in the GitHub Desktop application anyways. The question is thus: what does this prompt do?</p>
  
  <p><a href="https://i.stack.imgur.com/t0VgT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/t0VgT.png" alt="The prompt"></a></p>
  
  <p><a href="https://i.stack.imgur.com/7gPgi.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7gPgi.png" alt="After prompt - showing results"></a></p>
  
  <p><a href="https://i.stack.imgur.com/BzCqX.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BzCqX.png" alt="Git status"></a></p>
  
  <p>EDIT: Current set up:</p>
  
  <p>IntelliJ IDEA 2018.1 (Community Edition)
  Build #IC-181.4203.550, built on March 26, 2018
  JRE: 1.8.0_152-release-1136-b20 amd64
  JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
  Windows 10 10.0</p>
  
  <p>GitHub Desktop 1.2.6</p>
  
  <p>EDIT: Now updated IntelliJ to latest version:</p>
  
  <p>IntelliJ IDEA 2018.1.6 (Community Edition)
  Build #IC-181.5540.7, built on July 11, 2018
  JRE: 1.8.0_152-release-1136-b39 amd64
  JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
  Windows 10 10.0</p>
  
  <p>Here is a screenshot of the <code>gitstatus</code> (but both files still get listed in GitHub Desktop as being ready to be committed) : </p>
  
  <p><a href="https://i.stack.imgur.com/Kvnoe.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Kvnoe.png" alt="Latest version IntelliJ screenshot"></a></p>