You are not using the ObservableList. You are chan...

# tornadofx

[SiebelsTim]

You are not using the ObservableList. You are changing the contents of the property containing the list. The combobox never knows about the treatmentList property, therefore it cannot observe on it.
Try making treatmentList an ObservableList<String>. Then, you can do treatmentList.setAll(*it) in `runAsync`s ui block.