QColorDialog initial color lost after calling setOptions on Linux

If calling QColorDialog with an initial color (i.e. as initial arg to constructor), if

setOptions(QColorDialog::ShowAlphaChannel | QColorDialog::NoButtons | QColorDialog::DontUseNativeDialog);

is called afterwards, when the dialog is shown, the initial color isn't displayed on Linux. Works fine on Windows.

Workaround seems to be to call setCurrentColor after setOptions. But the docs don't appear to say that is necessary.