Motorola Z3 running Android 9.
Ratio pro version: 3.2.3:27
system volume slider overlay display will not disappear after a few seconds of inactivity. normally the pop up is closed automatically. Workaround is to touch screen away from object.
Also, on-screen YouTube video controls do not disappear after a few seconds without screen touch. Have to use the close button for it to go away.
Both seem related and actually could be by design due to how the launcher works.
Other than those minor issues, the launcher runs very well on this device.