supplementary_figures.tex

\documentclass[main.tex]{subfiles}
\usepackage{cleveref}
\usepackage{afterpage}
% \usepackage[nomarkers,figuresonly]{endfloat}

\begin{document}

\renewcommand{\figurename}{Supplementary Figure}
\renewcommand{\thefigure}{S\arabic{figure}}
\renewcommand{\thepage}{S\arabic{page}}

\renewcommand\floatpagefraction{.001}
\makeatletter
\setlength\@fpsep{\textheight}
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\title{Supplementary figures for the paper "The discovery of everything: all scientific problems solved"}
\maketitle

\listoffigures

\afterpage{\clearpage}
\begin{figure}[!p] 
\centering
\includegraphics[width=0.9\textwidth]{fig.eps}
\caption[Part of caption for the list of figures]{This is a widefig. This is an example of long caption this is an example of long caption  this is an example of long caption this is an example of long caption}\label{figS1}
\end{figure}

\afterpage{\clearpage}
\begin{figure}[!p] 
\centering
\includegraphics[width=0.9\textwidth]{fig.eps}
\caption[Main title of the figure]{This is a widefig. This is an example of long caption this is an example of long caption  this is an example of long caption this is an example of long caption}\label{figS2}
\end{figure}

\end{document}