Help - Extension Example Main-Menu does not add menu, just the command

I am trying to rewrite extensions I developed to work under classic jupyter notebooks to work with JupyterLab. I am trying to develop against version ^4. One of my needs are custom menus. I am trying to start with the main-menu extension example. The problem is the example does not add a menu, just the command and there are no obvious errors in the browser console.

When I do jlpm build I do get some warnings about where the crypto and webpack are provided. I assume that has to do with the @jupyterlab modules not being completely up-to-date on where things are in npm. So I do not think those are the problem. Could one of the example authors please suggest what is now failing?

Thanks,
Jonathan

I can partially answer my own question. The example is missing menu creation code from index.ts. I have sort of managed to cobble something together by pulling pieces from the lab base code and the non-working jupyterlab-snippets code. Is their a minimal example that does work? If I get this working properly I will make a pull request to correct the example.

It appears the example is expecting to load the settings from the schema in a .json file, but I cannot figure out how that is supposed to work within the structure of the example. I have managed to build a menu using code only in my own project. I will report an issue for the example.