Split view is flashing when keys are locked/unlocked

Preconditions:
Application includes QMainWindow with one QWidget that supports text input. Tested with QLineEdit and QTextEdit.
QLineEdit/QTextEdit position is on top, bottom or center of the screen.

Test steps:
1. open the split view by tapping the text input field.
2. when split view is open, press the lock/unlock key on side of the C7.
--> keys are locked and screen saver is visible
3. press again the lock/unlock key
--> keys are unlocked and split view is opened.

Expected result:
Split view is correctly drawn.

Actual result:
Split view flashes so that the application title pane is displayed. Also the QLineEdit/QTextEdit position on split view changes: it 'jumps' up or down depending of the original position.