Rated 2 out of 5 stars

The dictionary switcher slows down Thunderbird a lot while typing the text of your e-mail. It switches a lot during typing, also when I'm still typing the same language, this switching lasting for several seconds where nothing can been done but waiting which language the program will choose now. So unhappily, because the general idea behind it being smart, I switched off Dictionary Switch!

This review is for a previous version of the add-on (1.1.2).