QGroupBox title is cut off after modifying it

[c.buhtz at posteo.jp]

Hello,

I tried but I'm not able to create an minimal working example to
reproduce this. So I can only offer you a screenshot to illustrate my
problem. Maybe you have an idea or a hint what could it be or where to
look.

 https://i.imgur.com/QpIlbot.png

There is a QGroupBox which title is cutoff at the end. Not sure if
there is a QLabel behind it. But it looks like that the widget did not
expand to the full possible length.

Initially the title was short. After an event/signal the title was
modified with a longer string.

There are much more other widgets and layouts invovled. I assume that
one of them influence the groupbox behavior.

It is initialized like this in the QMainWindow

    self.filesWidget = QGroupBox(self)
    filesLayout = QVBoxLayout(self.filesWidget)

    # ...
    self.mainSplitter = QSplitter(Qt.Horizontal, self)
    self.mainSplitter.addWidget(self.timeLine)
    self.mainSplitter.addWidget(self.filesWidget)
  
As I stated I'm not able to reproduce in an MWE. My MWE works well.
Everytime I modify the string the groupbox resize itself and display
the whole string.

I'm confused.

Currently I can workaround it with just initializing the title with a
some blank spaces.

Kind
Christian