Presto, I'd say.
If an up-to-date 12 (12.18 etc., sec/compat patches), you just say so. If 11 or lower, we've already had a thread for those in the Lounge for some time, called "Opera 10-11 problems" (for even lower, it might be a special case each time such people come here).
The point being older versions (Presto) are severely outdated and neither maintained nor supported in any way. So well, yes, we use them, but at our own discretion, and can't ask for any official response there. Only old tweaks and tricks relying on other users.