As I understand, when 3e came out at first, certain rules-light supplements were to remain official until they were updated. Are there any such 2e supplements left? Just wondering
"Official"? I'm not sure what you mean here, or what you are referring to. In terms of rules, I don't think *anything* is "official" (whatever that means) anymore. Though probably, considering the edition change, no 2e rule would be considered "official".
If you're talking about campaign settings, yes - all previously published material is "official" until a newer product *specifically* prints contradicting info.
(Of course, any who subscribe to or care about *either* of the above has something wrong with them...)