How is addClass method supposed to work?

[utanashati]

Hi Vexflow team! Thank you for this great lib!

I have an issue with the addClass method, of a StaveNote, in particular. I tried using it on a StaveNote to add a custom class to the corresponding G element, and while after I use it, the StaveNote instance does get updated with the new class name, it's not reflected in the final SVG.

Could you please explain, is this a bug or a feature, and how is it supposed to work? At which point do the classes get appended to the G elements?

I reproduced the issue in a code sandbox.