QToolBar: How do you suppress the right-click menu that allows hiding the toolbar?

[ChrisW67]

How do you suppress the right-click menu that allows hiding a QToolBar ? The tool bars are part of a QMainWindow if that makes a difference.

Should be a very simple thing to do but my searches in the documentation have drawn a blank. I can see where the label text can be set and can set it to an empty string but the right-click option remains.

Cheers,
Chris W