Moving navigation bar to the bottom of the frame - Beamer latex, Frankfurt theme

Question

I would like to move the black navigation bar at the bottom of the frame.

How can I do that ?

Here is a screenshot of how it is right now :

I'm using the Frankfurt theme in overleaf :

\documentclass[11pt]{beamer}
\usetheme{Frankfurt}

Answer 1

Frankfurt uses the smootbars outer theme. You can copy the definition of the smoothbars headline and use it as footline:

(make sure your beamer version is reasonable up to date, I recently changed the code of the shading a bit to make them transparent, so the code below might not work correctly with old beamer versions)

\documentclass[11pt]{beamer}
\usetheme{Frankfurt}

\setbeamertemplate{headline}{}

\makeatletter
\setbeamertemplate{footline}{
  \pgfuseshading{beamer@barshade}%
  \vskip-0.05ex%
  \begin{beamercolorbox}[wd=\paperwidth,ht=1ex,dp=0ex]{empty}
  \begin{pgfpicture}
    \begin{pgfscope}%
      \ifbeamer@sb@subsection%
        \pgfsetfillcolor{subsection in head/foot.bg}%
      \else%
        \pgfsetfillcolor{section in head/foot.bg}%
      \fi%
      \pgfpathrectangle{\pgfpoint{-.5\paperwidth}{-0.5ex}}{\pgfpoint{\paperwidth}{1ex}}%
      \pgfsetfading{beamer@belowframetitlemask}{}%
      \pgfusepath{fill}%
    \end{pgfscope}%
  \end{pgfpicture}%
  \end{beamercolorbox}%
  \ifbeamer@sb@subsection%
    \vskip-9.75ex%
  \else%
    \vskip-6.85ex%
  \fi%
  \begin{beamercolorbox}[ignorebg,ht=2.25ex,dp=3.75ex]{section in head/foot}
    \insertnavigation{\paperwidth}
  \end{beamercolorbox}%
  \ifbeamer@sb@subsection%
    \begin{beamercolorbox}[ignorebg,ht=2.125ex,dp=1.125ex,%
      leftskip=.3cm,rightskip=.3cm plus1fil]{subsection in head/foot}
      \usebeamerfont{subsection in head/foot}\insertsubsectionhead
    \end{beamercolorbox}%
  \fi%
}
\makeatother
\begin{document}

\section{title} 
\begin{frame}
    abc
\end{frame} 
    
\end{document}