@8Observer8 said in QOpenGLFunctions glGetString(GL_EXTENSIONS) is null: I have a same question. I try to show OpenGL version but I get empty string: I solved the problem. I activated a second video card on my laptop from code in main.cpp: #ifdef _WIN32 #include <windows.h> extern "C" __declspec(dllexport) DWORD NvOptimusEnablement = 0x00000001; extern "C" __declspec(dllexport) DWORD AmdPowerXpressRequestHighPerformance = 0x00000001; #endif #include "Widget.h" #include <QApplication> int main(int argc, char *argv[]) { QApplication a(argc, argv); Widget w; w.show(); return a.exec(); } It works too (without QString::fromLatin1): qDebug() << (const char*)glGetString(GL_VERSION);