Why does \usepackage{amsmath} break \hyperref in \textnormal?

Question

In the following sample, the second link isn't hyperlinked:

\documentclass{article}

\usepackage{amsmath} % Removing this makes the second link work
\usepackage{hyperref}

\begin{document}
  \hyperref[abc-def]{link} % This link works
  \(\textnormal{\hyperref[abc-def]{link}}\) % But not this one
  \label{abc-def} Target
\end{document}

However, removing \usepackage{amsmath} fixes the second link. Why is that? And how can I make the second link work without removing amsmath?

(This is a simplified example from auto-generated XeLaTeX sources, so modifying the code itself is rather inconvenient).

Here is a slightly larger example:

\documentclass{article}

\usepackage{amsmath}
\usepackage{hyperref}

\begin{document}
\hyperref[lbl]{term}
\(\textnormal{\hyperref[lbl]{term}}\)

\newpage
\subsubsection{Abc}
\phantomsection\label{lbl} def
\end{document}

Answer 1

Update Fixed in Hyperref v6.83p

---

It appears that the macro code for xetex/dvipdfm(x) only inserts the link in the first choice of a mathchoice (so it works in displaystyle only)

You could use \mbox or a similar construct that forces text size so avoids the mathchoice internally or a possibly better fix is

here I disabled amstext package \iffirstchoice@ test so the macros can not tell that they are being executed four times. this is what you want when adding a hyperref special but it does mean that if you increment a counter, or make an index entry within \textnormal you will get 4 increments or index entries.

\documentclass{article}
\usepackage{amsmath}

\usepackage{hyperref}

\begin{document}

\makeatletter
\let\iffirstchoice@\iftrue
\let\firstchoice@false\relax
\makeatletter

\hyperref[lbl]{1term}
\(\textnormal{\hyperref[lbl]{2term}} x^{\textnormal{\hyperref[lbl]{3term}}}\)

\newpage
\subsubsection{Abc}
\phantomsection\label{lbl} def
\end{document}