When a process becomes active and the first operator action is to press a QPushBUtton this press get lost. From the 2nd press on everything works fine.

Defect: When a process becomes active and the first operator action is to press a QPushBUtton this press get lost. From the 2nd press on everything works fine.

This example project simulates mouse press events via xlib functions and reports the number of the received pressed() signals.
If the program is started and the MainWindow has the mouse pointer then every 3 seconds a mouse press event
is simulated and each received pressed signal is reported via qDebug.

It can be observed that the first button press didn't force a pressed() signal. To reproduce the issue
make sure that the mouse pointer is positioned at the location where the MainWindow will be appear because

• if the mouse pointer is not over the main window the press events will not reach the MainWindow
• if the mouse pointer is moved into the main window then the error can't be observed. The move event "fix" the issue.

The real issue appear on Touch Screen displays when a process opens a dialog and the first user action is a button press.