appConfig not setting all defaultProps values

Question

I am using the npm setup for the webchat and I need to override the the predefinedMessage value and a couple of other elements. In the documentation, it says that you can do this via the default props and the componentProps value in the appConfig can be used for these but for this one and a couple of others, that does not seem to be the case, it just seems to be ignored.

Is there any ideas why these values don't seem to work through the appConfig?

I have tried the setup like this in the componentProps value in the appConfig (other props work):

MessagingCanvas: {
    predefinedMessage: { // this with a capital P as well
      body: "Dummy text",
      authorName: 'dummyName',
      isFromMe: false, //tried without this
    },
  }

but this seems to just get ignored. But when I force it, like this in the App.js, it works:

FlexWebChat.MessagingCanvas.defaultProps.predefinedMessage = {
      body: "Dummy text",
      authorName: 'dummyName'
}