Wolfgang Wagner Cameo in Meistersinger (Did you know?)

Did you know that Wolfgang Wagner appeared in a cameo in the filmed Bayreuth Meistersinger from 1984? He stands in a long brown coat nest to Beckmesser (Hermann Prey). Had he done that (like Alfred Hitchcock in his movies) in every performance of the Wagner operas he directed at the Bayreuth Festival, more people would probably have stayed awake.