How do I jump to a specific date in history or the oldest message in a Slack channel in the desktop app?

Slack..version 2.0.0 has jump to date feature. on selecting a particular date, the control goes to that particular date and then we can scroll

Click the settings on the channel, and then "Jump to date ..."

In the desktop app, to jump to the oldest message one can open View Channel Details tab by clicking the (i) button, then clicking Created by ... text will take one to the first message in the channel