Comment 3 for bug 1517612

I am still investigating, but I verified that it will work properly when the app switches to the new header:

import QtQuick 2.4
import Ubuntu.Components 1.3

MainView {
    id: mainview
    objectName: "mainView"

    width: units.gu(100)
    height: units.gu(75)

    Page {
        id: mainPage
        header: PageHeader {
            title: "Should not select"
            extension: Sections {
                model: [ "first", "second", "third" ]
                selectedIndex: -1
            }
        }
    }
}