Unclear resizability behavior in QWizard

Different pages of a wizard can have different resizing policies: resizable only vertically but not horizontally, the other way around, resizable in both directions, or be fixed.

Reproducable with the dialogs/classwizard example. The "IntroPage" is only resizable horizontally, the following "ClassInfoPage" is resizable vertically. If I resize the dialog and switch between these two pages, the dialog resizes itself.