This example shows beamerappendixnote with a long note. The main frame has a link to a note whose content is longer, set in the appendix frame with lipsum text, and a Back button returns to the main content. It uses the same appxnote and printappxnotes commands as the short example and is helpful when you need to attach detailed derivations or extra data to a slide.
Shared under the LaTeX Project Public License 1.3c. All credit to Christoph Semken; the licence comes with the project's files.