No rendering with OpenGL 3 and above

[rjx-ray]

I have an app using ofxCef with of_v0.10.0_vs2017_release, VS2017, Windows 10.
I've been trying to update it to use openGL 4.6 instead of the 2.1 version that OF defaults to.
So I've changed the way that main.cpp starts up my App from

	ofAppGLFWWindow window;
	ofSetupOpenGL(&window, 1024, 768, OF_WINDOW);
	ofApp* p = new ofApp();
	p->cefgui = cefgui;
	ofRunApp(p);

to

	ofGLFWWindowSettings windowSettings;
	windowSettings.setGLVersion(4, 6); 
	windowSettings.setSize(1024, 768);
	windowSettings.resizable = true;
	ofAppGLFWWindow window;	
	shared_ptr<ofAppBaseWindow> mainWindow = ofCreateWindow(windowSettings);
	shared_ptr<ofApp> mainApp(new ofApp());
	mainApp->cefgui = cefgui;
	ofRunApp(mainWindow, mainApp);
	ofRunMainLoop();

Now my app uses ofGLProgrammableRenderer instead of ofGLRenderer and everything works except that the browser window is empty.
If I comment out line 24

#define NOGLDEBUG

in ofxCEFRenderHandler.cpp I see that every call to openGL in ofxCEFRenderHandler::init() results in glGetError() returning 1280 Invalid Enum so there is something pretty fundamentally wrong.

Everything works normally if I set the GL version to 2.1 in the windowSettings, but any version from 3.0 upwards gives me the issue.

If anyone has any insight into this issue I would really appreciate some help

Thanks,
Richard