I attached the example to reproduce the issue. It does not crash in Qt 6.7.3.

To crash just double click the button.

The bug occurred in a real world app that is not quite as dumb as this example - but this is what it took for me to reproduce it.

If the connection is not Queued or there is no ToolTip involved or the sleep_for is not in there it will not crash.

sleep_for is a standin for some application code that caused the required delay to fail. The Queued connection is there for threading reasons in the real app.