Currently on MacOS when I receive a direct message a red dot appears on the slack icon within the dock. I have my dock hidden for extra screen real estate, so rely on the bounce to notify me on incoming messages, however I don't always respond straight away. If I'm concentrating on something I would completely forget about it! (My team probably hate me for this).
When I use ubuntu however there is a slack icon in the top menu bar. I would like to see this feature as an option on the MacOS application. It would be a preferable reminder for me that a message is waiting to be read.
Attached is a poorly drawn example!