QT C++ GUI Tutorial 5- How to open a new window from a pushbutton in Qt

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c++ - How would I open a new window from a button in the main
How to show another window from mainwindow in QT
How to move to another window in Qt by a pushbutton
How to open a new window in Qt
Open new window when button on main-window is clicked
Open new window on menu action.
 QMainWindow open a new QMainWindow
Thread: Open a window inside another window
Thread: right way to open a new window
Open a window inside another window