title: Gnome Shell Integration in Firefox 51 not working
body: <p>I'm trying to use install an extension from <a href="https://extensions.gnome.org/" rel="nofollow noreferrer">https://extensions.gnome.org/</a> using Firefox 51 on 16.04. I followed the instructions and installed the Gnome Shell Integration as well as chrome-gnome-shell. However, when opening <a href="https://extensions.gnome.org/" rel="nofollow noreferrer">https://extensions.gnome.org/</a> I still get a hint to install the above:</p>
  
  <p><a href="https://i.stack.imgur.com/PaC9J.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PaC9J.png" alt="The problem."></a></p>