i have pity but for the record, this is what happens when you "go to next unread message" (and have unread messages in multiple channels) in Slack:
it scrolls the current channel list up, such that the current channel is on the bottom of the screen. but it's hidden behind the notification you are working to make go away, the more unreads indicator.
the mastodon instance at cybre.space is retired
see the end-of-life plan for details: https://cybre.space/~chr/cybre-space-eol