I understand that unread messages will remain gray until seen by the other person. I'm curious what qualifies as "seen". Does it mean that the other person has seen the notification (e.g. they've just activated their lock screen on iOS and have seen the toast, but haven't unlocked their phone and gone into Pair), or does it mean they've unlocked their phone and seen the toast in the notification bar up top, or does it mean they've actually gone into Pair app seen the message there?
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