This works very nicely, thanks a lot! The only thing missing in my view is (as in the Chrome equivalent) an extra option to press a trigger key to "Display pop-up when I select a word or phrase". Basically, I want the double-click to immediately translate a word and "CTRL+highlight the text" to translate an entire phrase. Would that be possible?

so usefull!

You're amazing super job. Thanks for this add ons

The best add-on for me which long time I was looking for. Thanks community. Keep it up-to-date.

Fixed the rating, absolutely phenomenal, very highly recommended

[EDIT] Originally had some issues in v1.0.5, but was able to get a bugfix merged and the developer is very responsive.

This addon is what I want exactly for a long time. Thank you.

This is really helpful and this tool is a must if you are looking for quick translations in the firefox browser. I do recommend!

Easy! Double-click word, get definition.

Finally I can ditch Chrome. Thank you for your service.

Was moving out of chrome for the good firefox offers and was terribly missing the 'google dictionary' extension. Thanks a 3000 for this add-on.

Dev, I don't know who you are but I love you...

...for this addon.

Edit:

A couple of things.
When double clicking a word in the popup, search that word too.
For some reason, it fails on the word "rapidly".

Excellent! The only criticism would be the "Searching... Please wait." screen. The lag is undesirable and could be worked on, but showing a "searching" screen makes it worse than it would look without such a note.