Mark messages as unread in the Unibox

We'd love the ability to manually mark a conversation as unread in the Unibox.

Right now, opening a conversation automatically marks it as read. If you open a message but aren't ready to reply, there's no way to re-flag it, so it's easy to lose track of conversations that still need action.

With a "Mark as unread" option, you could re-flag any conversation and have it resurface as unread until you're ready to deal with it, keeping your inbox accurate and nothing slipping through the cracks.