\documentclass[12pt,twoside]{memoir}
\usepackage{etoolbox}
\usepackage{luacode}
\usepackage{xcolor}
\usepackage{lipsum}
\usepackage{hyperref}
\usepackage{tcolorbox}
\tcbuselibrary{breakable,skins}
\usepackage{memoir-tcolorbox}

\paragraphfootnotes
\setlength{\footskip}{3\baselineskip}
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\renewcommand{\footnoterule}{}

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\checkandfixthelayout

\makepagestyle{plain}
\makeevenfoot{plain}{}{\thepage}{}
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\begin{document}

\chapter{Two-Page Sidebar Collision Tests}

Each test starts with a page break and contains a sidebar with 1/3 page of footnotes. Sidebar content length is varied to find the collision point where the second page sidebar content overlaps with footnotes.

All sidebars have \texttt{reserve footnote space=false}.

\clearpage

\section{Test 1: Two Pages Worth of Content}

\begin{sidebarframe}[reserve footnote space=false]{Test 1}
\lipsum[1-5]

Content.\footnote{\lipsum[6-7]}\footnote{\lipsum[8-9]}\footnote{\lipsum[10-11]}

\lipsum[12-16]
\end{sidebarframe}

\lipsum[17]

\clearpage

\section{Test 2: Slightly More Content}

\begin{sidebarframe}[reserve footnote space=false]{Test 2}
\lipsum[18-22]

Content.\footnote{\lipsum[23-24]}\footnote{\lipsum[25-26]}\footnote{\lipsum[27-28]}

\lipsum[29-34]
\end{sidebarframe}

\lipsum[35]

\clearpage

\section{Test 3: Even More Content}

\begin{sidebarframe}[reserve footnote space=false]{Test 3}
\lipsum[36-40]

Content.\footnote{\lipsum[41-42]}\footnote{\lipsum[43-44]}\footnote{\lipsum[45-46]}

\lipsum[47-53]
\end{sidebarframe}

\lipsum[54]

\clearpage

\section{Test 4: Additional Content}

\begin{sidebarframe}[reserve footnote space=false]{Test 4}
\lipsum[55-59]

Content.\footnote{\lipsum[60-61]}\footnote{\lipsum[62-63]}\footnote{\lipsum[64-65]}

\lipsum[66-73]
\end{sidebarframe}

\lipsum[74]

\clearpage

\section{Test 5: More Content Still}

\begin{sidebarframe}[reserve footnote space=false]{Test 5}
\lipsum[75-79]

Content.\footnote{\lipsum[80-81]}\footnote{\lipsum[82-83]}\footnote{\lipsum[84-85]}

\lipsum[86-94]
\end{sidebarframe}

\lipsum[95]

\clearpage

\section{Test 6: Maximum Content}

\begin{sidebarframe}[reserve footnote space=false]{Test 6}
\lipsum[96-100]

Content.\footnote{\lipsum[101-102]}\footnote{\lipsum[103-104]}\footnote{\lipsum[105-106]}

\lipsum[107-116]
\end{sidebarframe}

\lipsum[117]

\clearpage

\section{Test 7: Beyond Maximum}

\begin{sidebarframe}[reserve footnote space=false]{Test 7}
\lipsum[118-122]

Content.\footnote{\lipsum[123-124]}\footnote{\lipsum[125-126]}\footnote{\lipsum[127-128]}

\lipsum[129-139]
\end{sidebarframe}

\lipsum[140]

\clearpage

\section{Test 8: Three Pages Worth}

\begin{sidebarframe}[reserve footnote space=false]{Test 8}
\lipsum[141-145]

Content.\footnote{\lipsum[146-147]}\footnote{\lipsum[148-149]}\footnote{\lipsum[150-151]}

\lipsum[152-163]
\end{sidebarframe}

\lipsum[164]

\section{Summary}

Tests progressively increase sidebar content length to find the critical point where footnotes collide with sidebar content on the second page when footnote space reservation is disabled.

\end{document}
