Unsupported private class QuarterPickerComponent. This class is visible to consumers via CalendarModule -> QuarterPickerComponent, but is not exported from the top-level library entrypoint. code example

Example: Unsupported private class . This class is visible to consumers via

# Error Unsupported private class fooComponent. This class is visible to consumers via barModule
# In angular 9 it complains becuase it wants you to add it to the public api 
# Add your component to public_api.ts
export * from './lib/components/some-me/some-me.component';