Editor: QOpenGLContext::swapBuffers() warning with Qt5
QOpenGLContext::swapBuffers() called with non-exposed window, behavior is undefined
According to this thread, we can not swap buffers for windows, which are not exposed to the window management system:
The problem is, if the window is shown in the application but it is not in the window management system, it is a non exposed window. You cant swap the buffer on it. You have to do the first draw after exposeEvent occurs or check if( !isExposed ) on window before you draw.
Edited by Andrei Kortunov