TypeError: Cannot read properties of undefined (reading 'traverse')

You are missing an import of the OpenGLScalarBarActor somewhere (or I am). @Sebastien_Jourdain I added the opengl scalar bar actor to the All and Geometry profiles but not to the OpenGL\index.js file as it is a private class (but needs to be added to the factory. My assumption is that the profiles would handle that but maybe people are not relying on them?