It's better to make the connection graphically and name the slot in a way that it gives more information about what it does instead of a vague information when it is triggered.
The second connection is done byHowever, why am I not able to see the 'second' connect() statement ? Is the statement hidden from us ?
QMetaObject::connectSlotsByName() that is called from setupUi() in the file generated by uic from your Designer form.
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