Translate to selected language on a per-site basis?

I miss being able to chose which language to translate to on a per-site basis AND the browser remember that setting. If you want to permanently translate to a specific language you have to change the preferred display language for all websites as I understand it. Actually it would suffice to be able to set a standard language to translate to, but independent of the preferred display language.

I know Firefox Translate is still Beta so perhaps this important enhancement is in the pipeline?