Hello All:

I'm using Qt Designer to create a Windows Form which I save as window.ui and then use it from PyQt5. Problem is the Preview in Qt Designer and the "real" window differs substantially... I would expect the final GUI be pretty close as the one Qt Designer shows in the Preview...
In the following screenshot, the window at the left is the "real" one while the right shows the Preview from Qt Designer;


This is the code I'm using to import the "window.ui" file;

class Window(QtWidgets.QMainWindow):
def __init__(self):
super(Window, self).__init__()
uic.loadUi("window.ui", self)

if __name__ == "__main__":
app = QtWidgets.QApplication([])
win = Window()

Any idea why this happens? Should I configure something else?

Thanks in advance;