Rated 4 out of 5 stars

le 22009 ar DFómh. 1, 2013 · buan-nasc

It is not a bug in the add-on itself which makes it not working properly anymore (unless you apply the tweaks mentioned in earlier comments).
As long as bug https://bugzilla.mozilla.org/show_bug.cgi?id=843727 is not fixed, this add-on will continue to have problems. The bug affects a core add-on interface that is out of control for the programmer(s) of dictionary switcher.