Some features like QWidget.size are defined by Qt with a non-standard setter name. For size, the standard setter name would be setSize, and in the property creation process this setter would be deleted. We changed rules in this way: If a setter name is non-standard (like resize), the setter will not be removed but still can be used. Actually it would make more sense if "size" was a read-only property. Task-number: PYSIDE-1019 Change-Id: I9ded7e9c1dbd2932aa4c5616385b90ed673bfaee Pick-to: 5.15 Pick-to: 6.0 Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>