The position property (string) specifies the bubble position relative to the source object.
The bubble will always try to fit into the current browser window. The position will be adjusted accordingly - in that case it doesn't have to follow the position value exactly.
The "Above" value is available since version 2020.1.4245. In prior versions, use "EventTop". The legacy "EventTop" value will be translated to "Above" in the latest version.
"Above"
const bubble = new DayPilot.Bubble({ position: "Mouse", // ... });