\documentclass[12pt,dvipsnames]{beamer}

\usepackage[utf8]{inputenc}

\usepackage{pgfpages}

\setbeameroption{show notes on second screen=right}
\usetheme[progressbar=frametitle]{metropolis}
% \usepackage{appendixnumberbeamer}
\setbeamercolor{block title example}{fg = mDarkTeal}
\AtBeginEnvironment{exampleblock}{\setbeamercolor{itemize item}{fg =
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\setbeamertemplate{caption}[default]

\newcommand{\resetcolor}{\def\currcolor{mDarkTeal}}
\newcommand{\currcolor}{}
\resetcolor
\setbeamercolor{frametitle}{bg=\currcolor}
\setbeamercolor{section title}{fg=\currcolor}

\usepackage{color}

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\newcommand{\orange}[1]{{\color{orange}{#1}}}
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\usepackage{amsmath}
\usepackage{amsfonts}

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\usepackage{tikz}
\usepackage{forest}
\usepackage{tikz-cd}
\usetikzlibrary{arrows}
\usetikzlibrary{shapes.geometric}
\usetikzlibrary{positioning}
\usetikzlibrary{matrix}
\usetikzlibrary{calc}
\usetikzlibrary{decorations.pathreplacing}
\usetikzlibrary{decorations.pathmorphing}
\usetikzlibrary{plothandlers}
\usetikzlibrary{decorations}

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  alt/.code args={<#1>#2#3}{%
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}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% absolute positioning of typeset material
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% https://tex.stackexchange.com/questions/311007/change-package-option-overlay-from-textpos-package-in-document/311031#311031
\newcommand{\placetextbox}[4][center]{%
  % [#1]: box anchor: center (default) |
  % south west | west | north west | north |
  % north east | east | south east | south |
  % mid west | mid | mid east |
  % base west | base | base east
  % #2: horizontal position (fraction of page width)
  % #3: vertical position (fraction of page height)
  % #4: content
  %
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}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% Useful shortcuts for math fonts
\newcommand{\ms}{\mathsf}
\newcommand{\mb}{\mathbf}
\newcommand{\mi}{\mathit}
\newcommand{\mt}{\mathtt}
\newcommand{\mc}{\mathcal}
\newcommand{\mf}{\mathfrak}

\title{TITLE}
\subtitle{SUBTITLE}
\date{CONFERENCE}
\author{Ryan Kavanagh}
\institute{Carnegie Mellon University}

\newenvironment<>{question}[1]{\begin{exampleblock}{Question}{#1}}{\end{exampleblock}}
\newenvironment<>{fact}[1]{\begin{exampleblock}{Fact}{#1}}{\end{exampleblock}}
\newtheorem{proposition}[theorem]{Proposition}

\newcommand{\nti}[1]{\note[item]{#1}}
\newcommand{\tikzmark}[1]{\tikz[remember picture] \node[coordinate] (#1) {#1};}

\tikzset{node/.style = {align=center,draw=\roran, very thick,
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\usepackage{etoolbox}

\begin{document}

\maketitle

\begin{frame}[t]
  \nti{A Note}
  \frametitle{A Title}
\end{frame}

% To change the theme colour to, e.g., lavender:
% \renewcommand{\currcolor}{lavender}
% To reset it:
% \newcommand{\resetcolor}{\def\currcolor{mDarkTeal}}

\begin{frame}[allowframebreaks]
  \frametitle{Related Work}

  \begin{thebibliography}{abcdef}

  \bibitem[AJ95]{AJ95}
    Abramsky, Samson and Achim~Jung.
    \newblock Domain Theory
    \newblock {\em Handbook of Logic in Computer Science}. Vol 3, 1995.

  \bibitem[BE]{BE}
    Bloom, Stephen L. and Zolt{\'a}n {\'E}sik.
    \newblock Some Equational Laws of Initiality in {2CCC}'s
    \newblock {\em International Journal of Foundations of Computer
      Science}, \textbf{6}(2):95-118, 1995.

  \bibitem[F94]{F94}
    Fiore, Marcelo P.
    \newblock Axiomatic Domain Theory in Categories of\\
    Partial Maps
    \newblock PhD thesis. The University of Edinburgh, 1994.

  \end{thebibliography}
\end{frame}

\end{document}