title: Digitally signed JavaScript files
body: <p>I've come across some (Microsoft generated) JavaScript files that look like this:</p>
  
  <pre><code>... SOME JAVASCRIPT CODE...
  
  // SIG // Begin signature block
  // SIG // MIIaVgYJKoZIhvcNAQcCoIIaRzCCGkMCAQExCzAJBgUr
  ...
  // SIG // 2Ee3yfXCMiZKY8Yv2h0=
  // SIG // End signature block
  </code></pre>
  
  <p>My question is what is the purpose of this digital signature? Yes, I know it is signed with someone's public key and that it helps to identify the author of the file, and yes, I know that it also makes sure nobody has tampered with the file, but what do browsers do with it? How do they use it? What're the benefits of having it in your JavaScript file (besides making your files look much larger :)?</p>