SUMMARY
Most notably it doesn't honor individual alignment, causing much sadness because you can't have a toolbar where a number of buttons are left and the remainder right aligned. I may be doing it wrong though (:

```
Kirigami.ActionToolBar {
        alignment: Qt.AlignRight
        actions: [ Kirigami.Action {
                Layout.alignment : Qt.AlignLeft
                id: advancedAction
                checkable: true
                iconName: "code-context"
                text: i18nc("@action:button", "Show backtrace content (advanced)")
            },
            Kirigami.Action {
                enabled: trace !== ""
                iconName: "go-next"
                text: i18nc("@action:button", "Next")
                onTriggered: pageStack.push("qrc:/ui/BugzillaPage.qml")
            }
        ]
    }
}
```

As a workaround one can have a rowlayout with two bars aligning right and left respectively - It is awkward though because collapsing into a burger menu is then undefined behavior (as to which bar collapses)