Behaviour on is not executed when value change through a PropertyAction

The following code does not execute the Behaviour on opacity:

[...]

transitions: [
Transition {
PropertyAction

{ target: closeButton; properties: "opacity"; value: 1 }

}
]

[...]

Image {
id: closeButton
source: "foo.png"
opacity: 0

Behavior on opacity {
NumberAnimation

{ duration: 2000 }

}
}

[...]

Whereas replacing the PropertyAction by:
ScriptAction { script:

{ closeButton.opacity = 1; }

}

Executes the Behaviour correctly.