System posts: - " LEFT THIS MESSAGE X MINS AGO"

ahhh. Okay. Thanks.

Would probably be better to say

  • “@User unsubscribed from this Personal Message X minutes ago” or,
  • “@User departed from this message X minutes ago”

Because “User left this message” sounds like it’s confirming when they wrote a message.

“Leaving a message” doesn’t usually refer to someone departing.