Installed in Fx 52.3.0 x86_64 for Ubuntu 14.04.5 . Not only did this not work, but it brought up my browser console and threw a bunch of errors.

Un-installed.

It is good and very good idea overall but on some sites you will face problem using this as it can crash a site or force you to reload it..

really cool have been looking for a tool like this! keep tweaking and taking suggestions, nearly top-notch!

It works, but try to add some hotkeys