title: Why are global variables suddenly available for Greasemonkey and Tampermonkey scripts?
body: <p>Recently while writing a userscript and I found out that variables in the page context are available.<br>
  <code>console.log(window)</code> did not result in an error in neither Tampermonkey nor Greasemonkey. </p>
  
  <p>I am confused. Shouldn't global variables only be accessible through <code>unsafeWindow</code>?</p>