Customizing web widget text color in the header when using messaging

We are using the web widget with messaging/answer bot functionality.

The color of the heading of the widget is able to be customized, as well as the bubble that the customer text is in, and the color of the buttons, but I would like to be able to customize the font color as well.

For example, right now we have blue background with a black text for the widget header, we would like that to be either blue background with white text or white background with blue text. At present, the text color cannot be changed.

This would allow us to bring it more in alignment with our branding.  When we were using the classic widget, we were able to control the text color to keep it aligned with our branding.