Demonstrating a problem using marked through a library. This is a simple create-react-app to reproduce the problem, with an app (my-app) using a library (my-lib).
Within my-app, run yarn && yarn start. This tests using marked locally (within my-app) and through a library (in my-lib). The results are displayed in the web page:
That is, it fails only when imported through a library, with TypeError: Cannot read properties of undefined (reading 'parse').