Botões de hiperlinks em uma segunda camada em relação ao conteúdo do quadro

Question

No quadro a seguir, a linha de rodapé com botões de hiperlinks se sobrepõe a duas imagens:

Existe uma maneira de declarar no preâmbulo que o rodapé do hiperlink está em uma segunda camada (fundo) em relação ao conteúdo de cada slide?

Código:

\documentclass{beamer}
%
%
\usepackage[english]{babel}
\usepackage{multirow}
\usepackage{amsmath}
\usepackage[]{hyperref}
\newcommand{\btVFill}{\vskip0pt plus 1filll}

\usepackage{totcount}
\regtotcounter{section}

\newcommand\Fontvi{\fontsize{6}{5.2}\selectfont}

% Format of the title of every section:
\AtBeginSection[]{\label{sec:\thesection}
  \begin{frame}{Outline}
       \tableofcontents[
         currentsection,
         sectionstyle=show/shaded,
         subsectionstyle=shaded/shaded/shaded,
         subsubsectionstyle=shaded/shaded/shaded/shaded
         ]
  \end{frame}
}

\newcounter{prevsec}
\setbeamertemplate{navigation symbols}{}

% Create footline: 
\setbeamertemplate{footline}{%
        \setcounter{prevsec}{\thesection}
        \ifnum\theprevsec>1
            \addtocounter{prevsec}{-1}
        \fi

    \quad\hyperlinkpresentationstart{\beamerreturnbutton{Back to start}}%
    \quad\hyperlinksectionstart{\beamerreturnbutton{Back to section start}}%
%   \quad\hyperlink{moredetails}{\beamergotobutton{More details}}%
    \ifnum\thesection<\totvalue{section}%
        \quad\hyperlinksectionstartnext{\beamerskipbutton{Next section}}%
    \else%
        \quad \beamerskipbutton{Next section}%
    \fi%
    \quad\hyperlink{sec:\theprevsec}{\beamerskipbutton{Previous section}}%
    \vspace*{0.2cm}%
}


% Outline at the beginning of each subsection:
\AtBeginSubsection[]
{
    \begin{frame}{Outline}
        \tableofcontents[currentsection,currentsubsection]
    \end{frame}
}

% Outline at the beginning of each subsubsection:
\AtBeginSubsubsection[]
{
    \begin{frame}{Outline}
        \tableofcontents[currentsection,currentsubsection]
    \end{frame}
}

\begin{document}

   \section{sec1}
    \begin{frame}%{ss}
    1st section/ page 1 out of 1
    \end{frame}

    \begin{frame}
    1st section/ page 2 out of 2
    \end{frame}

    \begin{frame}[label=Detailed_Analysis]
        Detailed Analysis
    \end{frame}

    \section{sec2}

\def\Blablabla{

%Some text, some text some text
  \begin{enumerate}
\Fontvi
  \item Some text: Some info
  \item Some other text: Some other info
  \end{enumerate}
}
%
\begin{frame}%[plain]
%
\begin{table}
\centering
%\vspace{-1em}
\begin{tabular}{c|c|c|c|c}
$A$ & $B$ & $C$ & $D$ and $E$  \\\hline
$1.1$ & $1.2$ & $1.3$ & $1.4$ & $1.5$
\end{tabular}
%\caption{\label{tab:widgets}An example table.}
\end{table}
\vspace{-0.5em}
%
\centering
\includegraphics[width=.48\linewidth]{example-image}
\begin{minipage}[b][0.4\textheight][c]{.45\linewidth} \Blablabla \end{minipage}\\[1em]
\includegraphics[width=.48\linewidth]{example-image}\quad
\includegraphics[width=.48\linewidth]{example-image}
\end{frame}

    \section{sec3}
    \begin{frame}
    3rd section
    \end{frame}

    \begin{frame}
    More content on the 3rd section
    \end{frame}

    \begin{frame}
    Even More content on the 3rd section
    \end{frame}

    \end{document}

Atualizar: O código acima postado na pergunta tem a funcionalidade de exibir o contorno toda vez que mudamos de seção. Ao exibir esse contorno, também é possível pular para a seção selecionada clicando sobre ela. Por exemplo, se terminamos a seção 1, o próximo slide é o esboço destacando a próxima seção 2, e também existe a possibilidade de clicar na seção desbotada 3 para pular para a seção 3:

Ao usar a resposta @samcarter, agora o esboço ainda aparece ao iniciar uma nova seção, mas a funcionalidade de clicar no nome da seção para pular para aquela seção está desabilitada, conforme mostrado nestecódigo 2:

\usepackage[english]{babel}
\usepackage{multirow}
\usepackage{amsmath}
\newcommand{\btVFill}{\vskip0pt plus 1filll}

\usepackage{totcount}
\regtotcounter{section}

\newcommand\Fontvi{\fontsize{6}{5.2}\selectfont}

\newcounter{prevsec}

\setbeamertemplate{footline}{}
\setbeamertemplate{navigation symbols}{}

\makeatletter
\setbeamertemplate{sidebar canvas left}
  {%
  \tiny%
  \leavevmode%
  \hbox{%
  \rule{0pt}{.99\paperheight}%
        \setcounter{prevsec}{\thesection}
        \ifnum\theprevsec>1
            \addtocounter{prevsec}{-1}
        \fi

    \quad\hyperlinkpresentationstart{\beamerreturnbutton{Back to start}}%
    \quad\hyperlinksectionstart{\beamerreturnbutton{Back to section start}}%
%   \quad\hyperlink{moredetails}{\beamergotobutton{More details}}%
    \ifnum\thesection<\totvalue{section}%
        \quad\hyperlinksectionstartnext{\beamerskipbutton{Next section}}%
    \else%
        \quad \beamerskipbutton{Next section}%
    \fi%
    \quad\hyperlink{sec:\theprevsec}{\beamerskipbutton{Previous section}}%
    \vspace*{0.2cm}%
        }%
  \vskip0pt%
  }
\makeatother
%
% Outline at the beginning of every section:
\AtBeginSection[]{\label{sec:\thesection}
  \begin{frame}{Outline}
       \tableofcontents[
         currentsection,
         sectionstyle=show/shaded,
         subsectionstyle=shaded/shaded/shaded,
         subsubsectionstyle=shaded/shaded/shaded/shaded
         ]
  \end{frame}
}

% Outline at the beginning of each subsection:
\AtBeginSubsection[]
{
    \begin{frame}{Outline}
        \tableofcontents[currentsection,currentsubsection]
    \end{frame}
}

% Outline at the beginning of each subsubsection:
\AtBeginSubsubsection[]
{
    \begin{frame}{Outline}
        \tableofcontents[currentsection,currentsubsection]
    \end{frame}
}

\begin{document}

   \section{sec1}
    \begin{frame}%{ss}
    1st section/ page 1 out of 1
    \end{frame}

    \begin{frame}
    1st section/ page 2 out of 2
    \end{frame}

    \begin{frame}[label=Detailed_Analysis]
        Detailed Analysis
    \end{frame}

    \section{sec2}

\def\Blablabla{

%Some text, some text some text
  \begin{enumerate}
\Fontvi
  \item Some text: Some info
  \item Some other text: Some other info
  \end{enumerate}
}
%
\begin{frame}%[plain]
%
\begin{table}
\centering
%\vspace{-1em}
\begin{tabular}{c|c|c|c|c}
$A$ & $B$ & $C$ & $D$ and $E$  \\\hline
$1.1$ & $1.2$ & $1.3$ & $1.4$ & $1.5$
\end{tabular}
%\caption{\label{tab:widgets}An example table.}
\end{table}
\vspace{-0.5em}
%
\centering
\includegraphics[width=.48\linewidth]{example-image}
\begin{minipage}[b][0.4\textheight][c]{.45\linewidth} \Blablabla \end{minipage}\\[1em]
\includegraphics[width=.48\linewidth]{example-image}\quad
\includegraphics[width=.48\linewidth]{example-image}
\end{frame}

    \section{sec3}
    \begin{frame}
    3rd section
    \end{frame}

    \begin{frame}
    More content on the 3rd section
    \end{frame}

    \begin{frame}
    Even More content on the 3rd section
    \end{frame}


\end{document}

Atualização 2:Além disso, o pdf gerado comcódigo 2parece ter funcionalidades de vinculação erradas, por exemplo, se eu abrir o pdf na página 2, se localizar o mouse em algum lugar na área certa, uma Go to page 1informação aparecerá:

e se eu clicar, sou redirecionado para a página 1.

Isso estava acontecendo okular. O mesmo acontece se eu abrir o documento com evince:

Answer 1

Os botões parecem ainda clicáveis, mas você terá que adivinhar onde eles estão.

\documentclass{beamer}

\usepackage{totcount}
\regtotcounter{section}

\newcounter{prevsec}

\setbeamertemplate{footline}{}
\setbeamertemplate{navigation symbols}{}

% Format of the title of every section:
\AtBeginSection[]{\label{sec:\thesection}
  \begin{frame}{Outline}
       \tableofcontents[
         currentsection,
         sectionstyle=show/shaded,
         subsectionstyle=shaded/shaded/shaded,
         subsubsectionstyle=shaded/shaded/shaded/shaded
         ]
  \end{frame}
}


\makeatletter
\setbeamertemplate{sidebar canvas left}{%
    \begin{minipage}[t][.98\paperheight][b]{\textwidth}
      \tiny%
      \setcounter{prevsec}{\thesection}
      \ifnum\theprevsec>1
        \addtocounter{prevsec}{-1}
      \fi
        \quad\hyperlinkpresentationstart{\beamerreturnbutton{Back to start}}%
      \quad\hyperlinksectionstart{\beamerreturnbutton{Back to section start}}%
        \ifnum\thesection<\totvalue{section}%
        \quad\hyperlinksectionstartnext{\beamerskipbutton{Next section}}%
      \else%
        \quad \beamerskipbutton{Next section}%
      \fi%
      \quad\hyperlink{sec:\theprevsec}{\beamerskipbutton{Previous section}}%
    \end{minipage}   
}
\makeatother

\begin{document}

  \section{sec1}
    \begin{frame}%{ss}
    1st section/ page 1 out of 1
    \end{frame}

    \begin{frame}
    1st section/ page 2 out of 2
    \end{frame}

    \begin{frame}[label=Detailed_Analysis]
        Detailed Analysis
    \end{frame}

    \section{sec2}
%
\begin{frame}%[plain]
%
\begin{table}
\centering
%\vspace{-1em}
\begin{tabular}{c|c|c|c|c}
$A$ & $B$ & $C$ & $D$ and $E$  \\\hline
$1.1$ & $1.2$ & $1.3$ & $1.4$ & $1.5$
\end{tabular}
%\caption{\label{tab:widgets}An example table.}
\end{table}
\vspace{-0.5em}
%
\centering
\includegraphics[width=.48\linewidth]{example-image}
\begin{minipage}[b][0.4\textheight][c]{.45\linewidth} \end{minipage}\\[1em]
\includegraphics[width=.48\linewidth]{example-image}\quad
\includegraphics[width=.48\linewidth]{example-image}
\end{frame}

    \section{sec3}
    \begin{frame}
    3rd section
    \end{frame}

    \begin{frame}
    More content on the 3rd section
    \end{frame}

    \begin{frame}
    Even More content on the 3rd section
    \end{frame}


\end{document}