QComboBox cannot automatically close the shown list if clicked again on its extend button.

Test code shown below.

QStringList fonts;
fonts << "Arial" << "Helvetica" << "Times" << "Courier";
QComboBox draftComboBox;
draftComboBox.addItems(fonts);
draftComboBox.show();

After clicking the button to show the drop-down list, you should be able to click it a second time to close the list.

The issue cannot be reproducible with Qt 4.8.5 environment.