Color dialog keeps growing vertically

Each time the color selection dialog is raised, it grows vertically, eventually making it hard to use when the buttons get pushed off the bottom of the screen.

Steps to reproduce:
1. Launch Qt Creator
2. Create a new widgets-based application
3. Add any widget to the initial form.
4. Select the widget from #3, and in the Properties pane, click the "Change Palette" button for the palette property.
5. In the palette dialog, double click on a role color, i.e. WindowText.
6. The color dialog appears, hit enter or pick a color and hit enter, doesn't really matter.
7. Repeat steps 5-6 several times.

Each time you execute step #5, the dialog grows vertically by some amount. The dialog CANNOT be resized using the mouse to make it smaller vertically. It can be resized larger vertically, but that only exacerbates the problem the next time you do #5. Eventually the widget will take up the entire vertical size of the monitor, making some parts unusable (i.e. the area where you can drag/drop favorite colors).

There appears to be no way to recover from this problem other than Quit QtCreator and relaunch.

I've included a test application which does NOT exhibit the same behavior, so it doesn't appear to be a problem with the QColorDialog itself but something QtCreator is doing with it.