title: How can I test if an autoprefixer is working?
body: <p>I am currently trying to set up the <a href="https://www.npmjs.com/package/autoprefixer" rel="noreferrer">autoprefixer npm package</a>. I would like to insert some css to see if it adds vendor prefixes as needed. However, I'm not sure what css I would add that would trigger an automatic vendor-specific insert. </p>
  
  <p>How might I figure out what css I could use to confirm that the package is working?</p>
  
  <p>For example, if I am using OSX Chrome v49.x, what would I use?</p>