Title pretty much says it all. /dd doesn't recognize I have a Mythic Sword in my inventory when it is in a magic shulker. Back when it was a sell prestige, the sell bonus worked when it was in there.
With that being said, idk if I am getting double drop bonuses from a mythic sword in my magic shulker. And for that, I am not sure if any boosted/magic items are working through a magic shulker
Evidence:
/dd
Showing my mythic sword is in my magic shulker, first slot to be specific