Rated 5 out of 5 stars

Works very well, but like for another reviewer it only worked after install, after browser restarted the toolbar icon disappeared on FF52.2.1 ESR
But, after few more restarts it appeared again an so far worked good.

Two suggestions though:
1) add option to the popup to open options
2) make toolbar button as button with an arrow dropdown, where pressing the button does user defined default action, and clicking on arrow opens additional options (just like it is now)