QTabWidget tab subcontrol position with qss

[alexandernst]

I want to put tab-bar at the bottom of the qtabwidget, and I'm trying to do it with this code:

QTabWidget::tab-bar {
  position: absolute;
  subcontrol-origin: margin;
  subcontrol-position: center bottom;
}

QTabWidget::tab-bar {
  position: absolute;
  subcontrol-origin: margin;
  subcontrol-position: center bottom;
}

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but it won't work.
Where is the error?

P.S: I know that this is possible to be done with .setTabPosition, but I want to do it with qss