I think this would be a pretty simple and straightforward addition to the current setup, but might have a lot of fun emergent behavior in the players meta-game. Currently in my 5e game we have an interesting smattering of languages, skills, and other perceptive abilities. It would be really great if DM's could add additional 'hidden' information to items that only certain characters could see when inspecting handouts or characters that have been added to their Journals. At the moment if I want to create a map or other item with language one character can read but perhaps others can't I must either create duplicate items, one with additional description, solely for those who can perceive this hidden information, or simply reveal it to all those who have it in their journal. This proposal would include a third description box to handouts/characters with an additional permissions field for those players able to see the 'hidden info' I'm particularly hoping this would help spark more player conversation and discussion as they determine whether anyone sees something the others don't, or perhaps even don't realize not everyone is privy to the same level of detail.