Notifications Stack On Top Of Each Other

Problem Statement

Currently when more than one notification occurs at a time, the most recent notification covers others up so that one can only view a single notification.

Expected Behavior

Like with Gnome Shell notifications, new notifications appear below existing notifications and when a notification goes away, any notifications below it move up to fill its space.

Steps to Reproduce

• notify-send test1 test1; notify-send test2 test2; notify-send test3 test3
• Note that they all quickly appear but only test3 is visible
• Tapping a notification makes it disappear and reveals notifications below it that haven't timed out.