I was attempting to implement the code from this question, but I have discovered that QTimer does not fire under certain circumstances.
The simplified code:
app = QApplication([])
view = QWebEngineView()
view.show()
def callback():
sys.exit(0)
QTimer.singleShot(1000, callback)
app.exec()
The application runs forever with this code (ie. callback is never executed). However, if you comment out view.show() then it exits after one second as it should.
As far as I can tell, this problem is particular to QWebEngineView; if we replace the QWebEngineView with a generic QWidget or QLabel, then it works as expected and exits after one second.
What is the cause of this, and how can I fix it?
As prompted by @eyllanesc, I have discovered that this is a bug introduced by the 5.14.0 release of the PyQtWebEngine module; the previous version (5.13.2) does not show this behavior.