Splitter sets fixed height

[cryzed]

Hello, I have the following Enaml code:

from enaml.widgets.api import MainWindow, MenuBar, Menu, Action, Container, Splitter, SplitItem, FlowArea, FlowItem, Label, Field

enamldef MainWindow(MainWindow):
    title = 'Serpens'
    MenuBar:
        Menu:
            title = '&File'
            Action:
                text = 'Import...'
            Action:
                separator = True
            Action:
                text = 'Exit\tCtrl+X'
                triggered :: exit()
    Container:
        background = 'green'
        Splitter:
            background = 'red'
            SplitItem:
                Container:
                    Label:
                        text = 'test'
            SplitItem:
                Container:
                    Label:
                        text = 'test'

which results in this: https://i.imgur.com/zEGZT4K.png. Can I get a tip/explanation why apparently the containers in the SplitItem suddenly start setting a fixed height? I expected the Container to take all available space, the Splitter as well and the SplitItems and their containers as well. Somehow it seems like the height is fixed to the smallest contained element now. Do I need to write custom constraints for this?

[cryzed]

I figured it out, it was the Field. When I set the constraints with `vbox(field, spacer)` in the parent container it works as expected.