This is their view of the canon:
catholicbridge.com/catholic/orthodox/why_orthodox_bible_is_different_from_catholic.php
In addition to this, there is the fact that Greek Orthodox Churches (especially) have a more fluid (less formal or legalistic) notion of how the idea of a “canonical book” should be applied. For example, in the Greek Orthodox Liturgy, they have NEVER read from the Book of Revelation. And, because of this, many modern Greeks will claim that Revelation is “not canonical.” …because they do not read from it in their Greek Liturgy. Now, the fact that the Russian Orthodox Church does read from Revelation in their, Russian Liturgy is beside the point. So, for the Eastern Orthodox, “canonical” does not really refer to a univesally-agreed upon canon, but to the common regional practice of specific Churches. Uunfortunately, this has led some modern Greek and Antiochian Orthodox to claim that the Book of Revelation is “not inspired” and/or “not binding” on them, which is a modernist revision (a heretical novelty), which no ancient Greek or Antiochian would ever claim. For, what their forefathers would say is that Revelation (or another book like it) is still Divinely inspired, but just not canonical (i.e., not approved for reading at their Liturgy). And, for those Easterners who did recognze the binding authority of the Cathaginian canon, they would of course say that Revelation is universally binding (i.e., canonical in a universal sense), but simply not part of their local Liturgical canon.