Drunk Mankiewicz, like many screenwriters of the talk show period, started out as a newspaperman. After the end of World War I, he was hired by the Parisian news service of the American Red Cross and then moved to the Chicago Tribune, where he covered German politics in Berlin. He worked as a publicist for dancer Isadora Duncan in Europe. Do you think he did not write music after that? I think the last thing he didn't do in his life was written music. I read about this in an essay about Herman Mankiewicz at https://assignmentbro.com/us/assignment-makers where I do various writing research and essay to order. And there seems to be even about music for films, but I did not hear exactly mention of the fact that he wrote the music himself, no one knows to the end.