How do I remove the icon from a ControlsFX ProgressDialog

Question

I have made a ProgressDialog using ControlsFX, got the service working, etc. All working fine.

The ProgressDialog shows a large blue "i" icon, plus the progress bar, plus header text etc.

How do I get rid of the blue "i" icon?

In a regular JavaFX dialog I can can get rid of the icon with this:

progress.initStyle(StageStyle.UTILITY);

But that doesn't seem to work for a ControlsFX ProgressDialog.

thx