Works with newer Mozilla programs too Rated 4 out of 5 stars

Said being incompatible with 24.3 Thunderbird, it seems to work fine. I recommend it to anyone despite the cons noted in previous review since there's no alternative at the moment.

Works perfectly on Windows and Ubuntu Rated 5 out of 5 stars

A very very useful plugin, works excellent in both Windows and Ubuntu, and in all versions of Firefox (that i have used so far).

One additional feature I am dreaming about is ability to automatically detect language. It's quite often a case when i write in Lithuanian in one tab, and then switch back to English. Constantly selecting spell checking plugin is quite a nuisance. I believe this feature request targets more whole Firefox app, than just this plugin.

This review is for a previous version of the add-on (1.2.1.20101118). 

Thanks!

Yep, what you want should be the app's functionality, not that of a dictionary (which I'm providing here mainly for the users of English versions of Firefox in Lithuania). Although, automatic language detection is not that easy, I guess. I think you may find it easier to develop a habit to use <Menu>→K→A and <Menu>→K→L to quickly change the dictionary in use without moving your hands away from the keyboard.

Though it's probably worth to file a feature request (if there isn't one) asking for Firefox to automatically choose a dictionary depending on the keyboard layout in use. It wouldn't cover all cases, but would at least be helpful in some.