Awesome
OmniSidebar
This add-on will not receive any more updates!
It will cease working by next November with Firefox 57. <a href="http://fasezero.com/lastnotice.html">Click here</a> for more info. Feel free to fork and use however you like.
AMO url: https://addons.mozilla.org/firefox/addon/omnisidebar/
Babelzilla page: https://www.babelzilla.org/index.php?option=com_wts&Itemid=0&type=show&extension=5563