Comment 16 for bug 1107859

I agree it's more of a firefox issue than a hyphen-ru thing, whatever we don to hyphen-ru would be a workaround. Still, I have a feeling firefox will take forever to be fixed…

I wouldn't like adding such a patch to lo-dicts, if such a thing would be needed there I'd try to do it a build time instead, and I'd do so very sadly.
Then, taking over a package in debian a kind of social problem :(, it needs to be done slowly and with great care, otherwise bad things may happen. If I were you in the meantime I'd
1) upload that hyphen-ru of yours to close this bug
2) open a bug against upstream lo-dicts to ask to convert the file to UTF-8