I have the same problem as siberianmario it doesn't work after last update :/ I have newest Firefox 60.0.1 (64 bit) for linux mint the same on windows ...

Сntl+C, Ctrl+V - ?

Yeap, still has some problems with 60.0.1 - can't neither translate with Shift+1, can't open preferences either.

simple, fast, accurate

Has some problems with twitter. Doble-click translation doesn't work anymore.

útil y bonito

Зручно користуватися

J'adore les infobules de traduction par un simple clic droit sur un texte sélectionné.

Ты хорош

Всплывающие окна очень удобны

a very must have ! .. except need to find better the language used... an other interface for the lightened word to translate. Most of time useful and .. usable !

Spot on and very easy to use. Thank you!

This add-on is very useful. I love phrase book and history features.
But it's quite inconvenience that I have to use combine key to see the translate popup, other add-on has a small bubble when you selected a word/words, I suggest you to do like them