Beamer notes slide aspect ratio

Question

I created a beamer presentation using aspectratio = 169 because 16:9 is the aspect ratio of the projector and my laptop's screen. I added notes to the presentation and the aspect ratio of the notes slides is also 16:9 (as expected and desired here).

However, the notes don't use all the available space on the notes slide. They only use an area corresponding to an aspect ratio of 4:3.

How can I make the notes use the whole 16:9 notes slide?

---

Minimal working example

\documentclass[aspectratio = 169]{beamer}
\setbeameroption{show notes}
\usepackage{lipsum}

\begin{document}
\begin{frame}
 \lipsum[1]
 \note{\lipsum[1]}
\end{frame}
\end{document}

---

Result

Regular slide

Notes slide

Answer 1

The problem is that the note page uses a hard coded text width of 10.8 cm.

This can be changed with the following redefinition:

\documentclass[
    aspectratio = 169
]{beamer}
\setbeameroption{show notes}
\usepackage{lipsum}

\makeatletter
\renewcommand\beamer@outsideframenote[2][]{%
  \beamer@savemode%
  \ifbeamer@inlecture%
    \def\beamer@noteenvstart{}%
    \def\beamer@noteenvend{}%
    \setkeys{beamernotes}{#1}%
    \ifbeamer@notes
    \begingroup
      \setbeamertemplate{itemize item}{\textbullet}
      \setbeamertemplate{itemize subitem}{--}
      \setbeamertemplate{enumerate item}{\insertenumlabel.}
      \setbeamertemplate{enumerate subitem}{\insertenumlabel.\insertsubenumlabel}
      \def\@oddhead{}
      \def\@oddfoot{}
      \let\@evenhead\@oddhead
      \let\@evenfoot\@oddfoot
      \def\beamer@backgroundtemplate{}%
      \setbeamercolor{item}{fg=black,bg=white}
      \color{black}%
      \nointerlineskip
      \hbox{\hskip-\Gm@lmargin\hskip1cm\vbox to\textheight{%
                                  %pretend to have ``standard'' margins
          \edef\beamer@origlmargin{\Gm@lmargin}%
          \edef\beamer@origrmargin{\Gm@rmargin}%
          \def\Gm@lmargin{1cm}%
          \def\Gm@rmargin{1cm}%
%          \textwidth=10.8cm%
          \hsize=\textwidth%
          \@arrayparboxrestore%
          \vskip-\headheight%
          \def\insertnote{\vbox{}%
            \beamer@noteenvstart#2\beamer@noteenvend%
          }%
          \usebeamertemplate*{note page}%
          \vfil%
          \vskip-4pt% foot separator
          \vskip-\footheight}\hskip-\Gm@lmargin\hskip1cm}%
      \ifbeamer@twoscreensnotes%
        \pgfpagescurrentpagewillbelogicalpage{2}%
        \advance\c@page by-1\relax%
      \fi%
      \clearpage
      \endgroup
    \fi%
  \fi%
  \beamer@resumemode}
\makeatother

\begin{document}
\begin{frame}
\frametitle{title}
\framesubtitle{subtitle}
 \lipsum[1]
 \note{\lipsum[1]}
\end{frame}
\end{document}

---

EDIT

This problem was fixed in the beamer development version with the commit e2ffe17 - it will probably be included in beamer version >=3.51