I have a 1950's copy of the Byzantine Rite and noticed that, in the Creed, it says that the Holy Spirit proceeds from the Father, without mentioning the Son. Moreover, when I've been to an Eastern Catholic service, they did not mention the Spirit proceeding from the Son either. Have Eastern Catholics never included the filioque in the Creed at all, or is this a new phenomenon?
I would imagine that this is just a strange indifferentism caused by the growing easternization of the Eastern Catholics, as is the veneration of "Saints" like Gregory Palamas. I can't seem to find anything about it online, though. Does anyone know more about this?