`hyperref` with `bookmarks=true` and `tikzexternalize` clashes in edge cases

Hey,

After having faced the same issue as https://github.com/borisveytsman/acmart/issues/436 when writing a paper with \documentclass{IEEEtran}, I decided to see which packages are related to the issue, and found that it's an interaction between hyperref's booktabs feature and tikzexternalize of tikz

MWE

Consider the following MWE (thanks @JasonGross for producing this).

%\PassOptionsToPackage{bookmarks=false}{hyperref} % This fixes the problem
\documentclass{acmart}
\usepackage{tikz}
\usepackage{pgfplots}
\usepgfplotslibrary{external}
\tikzexternalize
\begin{document}
\title{}
\begin{abstract} \end{abstract}
\maketitle
\section{XXXXXXXXX}\subsection{X XXXXXXXXXX XXXXXXX}\subsection{XXXXXXXX XX XXXXXXXXXXXXXXXXX XXXX}\subsection{XXX XXXXXXXX}
\section{XXXXXX XXXXXXXXXX XXX XXXXXXXXX}\subsection{XXX XXXXXXXX XX XXXX XXXXX}
\section{XXX XXXXXXXXX XX X XXXXXXXX}\subsection{XXXXXXXXXXXXXXXX XXXXXXXXXXX XXX XXXXXXXXXX}
\subsection{XXXXXX XXXXXXXXXXXX XXXXXXXX}
\section{XXXXXXX XXXXXXXXXX}\subsection{XXXXXXXX XXXXXXXXXXXX XXXX XX XXXXX}\subsection{XXXXXXX XXXXXXX XX XXXXXXX}
\subsection{XXXXX XXXX XXXX XXXXXXXXXX}\subsection{XXXX XXXXXXXXXX XXXX XXXXXXXX XXXXXXXXXXXXXX}
\subsection{XXXXXXXXXXX XXX XXXXXXXXXXXXX}
\section{XXXXXXXXXX}\subsection{XXXXXXXXXXXXXXX}
\begin{equation}\label{eq:equation}
    x+x^2
\end{equation}
\begin{tikzpicture}
    \begin{axis}
        \addplot [color=black,solid,line width=1.0pt,domain=0:1,samples=11]{x+x^2};
        \addlegendentry{Eq. \ref{eq:equation}};
    \end{axis}
\end{tikzpicture}
\subsubsection{XXXXXXXXX XXXXX XXXXXXX}\subsubsection{XXXXXXXXXXX XXXXXXXXXXX XX XXXXXXXXXXXXXXX XXXXXXXXX}
\subsubsection{XXXXXXX XXX XXXXXXXXX XXXXXXXXX}\subsubsection{XXXX XXXXXXXXX}\subsection{XXXXXXXXXXXXXXX XXXX XXXXXXXXXXXX}
\section{XXXXXXX XXXX}
\section{XXXXXX XXXX}
\end{document}

Compiling the above document with
docker run --rm -it --volume "`pwd`:/workdir" -w "/workdir" --user `id -u`:`id -g` registry.gitlab.com/islandoftex/images/texlive:TL2021-2022-01-09-04-05 pdflatex -shell-escape test.tex fails, and the ref used inside the tikzpicture is never resolved.
However, when providing \PassOptionsToPackage{bookmarks=false}{hyperref}, and thereby disabling the bookmarks functionality, the code compiles just fine and the ref is resolved properly.

Note that I also found the same clash to happen with \documentclass{IEEEtran}, which is why I guess that it's an interaction related between tikz and hyperref, rather than a problem with \documentclass{acmart}. Related package versions are,

Package: hyperref 2021-06-07 v7.00m
Package: tikz 2021/05/15 v3.1.9a (3.1.9a)

and full reproducibility should be given by the docker image.
Since I don't know the exact interactions which cause the issue and how to best resolve them, I have also crossposted the Issue to [tikz}(https://github.com/pgf-tikz/pgf/issues/1127).

Best,
ORippler

Start with the MWE in test.tex and reproduce it using the provided TeX Live Docker command. Compare compilation with bookmarks enabled and with PassOptionsToPackage disabling bookmarks, then investigate the hyperref and tikzexternalize interaction. Done means the reference resolves while bookmarks remain enabled.