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I'd like to keep track within Trello of things I've asked others to do, including clients, partners, etc. I can't really ask them to create a login in Trello just to help me. So is there a way to identify that this card is not for me to do something but actually for someone else, other than just putting their name in the title obviously ? Ideally, I'd like to be able to add them as "ghost member" or something like that. By the way, it would be nice to have a suggestion board in Trello itself where users can suggest things.