Saying Thanks Rated 3 out of 5 stars

Thank you so much very useful tool!

Also I suggest "Vocabulary Highlighter":
https://addons.mozilla.org/en-us/firefox/addon/vocabulary-highlighter/

Another one is not related but very handy "Print Pages to PDF":
https://addons.mozilla.org/en-us/firefox/addon/print-pages-to-pdf/

This review is for a previous version of the add-on (0.3.4).