QToolTip background cannot be styled without explicitly setting border

When a stylesheet is applied on a QToolTip the background will not get colorized. However the border will be. If the border property will be added explicitly to the stylesheet this problem doesn't appear anymore.

Here is an example stylesheet.

QToolTip {
  background: red;
  color: green;
}

A current workaround is. to set the border to none in the stylesheet.

The same code was tested on macOS 12.4 and it doesn't have the same problem.