Misleading error message from OpenGL renderer
In an OpenGL application that we recently ported to VTK 9.3.0 (www.MeVisLab.de), we use vtkExternalOpenGLRenderWindow to render into an existing OpenGL context (which already is a FramebufferObject). Initially an OpenGL INVALID_OPERATION was reported for the glBindFramebuffer operation. But this is wrong, the actually failing part was in glBlitFramebuffer, but the error code wasn't checked at that place, and then attributed to the next function where the error code was checked.
For my use case it was enough to add a call
vtkCheckOpenGLErrorsWithStack("glBlitFramebuffer");
to the end of vtkOpenGLState::vtkglBlitFramebuffer, but perhaps one should check other OpenGL methods too?