All Unreads (as the name may suggest…) is an option that gathers all your unread messages in one easily digestible, scrollable view. This way you can stay put and quickly scan what’s new, review what you need to, and clear the rest.
How it works
All the unread messages from your channels and direct message conversations are grouped together in a new All Unreads section at the top of your Slack sidebar.
Mark entire channels and DMs as “read” one by one, or click the “Mark All Messages Read” button at the bottom of the view to clear them all at once. If you want to save a channel or two to review later, leave them be and they’ll stay nice and bolded in your sidebar.
Don’t see All Unreads in your sidebar? Turn it on under Preferences > Advanced> Channel List > Turn on All Unreads (currently only available on desktop).