Application locks

The application locks when I arrange the mdi widgets.
I think this problem happens because the mouse position is wrong.

Basically, the mdi widget has a minimum size (ex. 400,400) and the main window is "frame theme" enabled. When I add four or more mdi widgets and arrange it, the main window is automatically resized. When this happen, the main window is moving.

In RibbonMdi example:

add "ribbonBar()->setFramThemeEnabled()" in mainwindow.cpp
add "this->setMinimumSize(400,400)" in texteditchild.cpp

Steps to reproduce:

The error has been reproduced. Thanks for the info. It will be fixed soon.

It still locks under different os (Win XP or Windows 7);
it locks if the window/mainwindow is not maximized.

If it locks on a system it doesn't always lock but 2 of 3 starts of the application... and
when it locks the hover effect of the buttons is visisble but no reaction to any input
neither lineedit nor button.

I'm using the qtnribbon version 2.8.1 and setFramThemeEnabled(); if I disable this feature or doesn't call the function everything works fine.

If the setFramThemeEnabled is enabled and the window is not maximized I have ugly lines around
the window (if you like i can make a screenshot); don't know what I'm doing wrong - I'm using
the code for building my ribbon application from the 'old' ribbon example 2.1.

Thanks for you help.

Frank