I have a public (e.g. no sign-in permissions required) Google Photo gallery (https://photos.google.com/u/1/share/AF1QipMprZKlgpg-x5WjqQYOP95qV6Db9gBAw2o5gDWQDkayqFx0o0EdPXHqnlwdVsuldw) and I am trying to embed it in an iFrame.