When I push the Android menu button (bottom left) in Dictionary, Flashcards, Clip Reader and Settings I get an empty menu with four blanc item boxes. Not when I push it in History, Live OCR or Add-ons.
I don't believe those screens have any options menu options, actually - what are you expecting the menu button to do? There's an option in Settings / Miscellaneous to make it open the drawer menu on the side, that seems to be problematic on newer versions of Android but should work fine on 4.2.
Actually I do not miss any specific options there. I just thought the empty item boxes look weird, like a bug. I guess I had expected no menu at all would appear if there were no options to choose from. But never mind... I don't really care. Thanks for the feedback though.