Fix duplicate frame classes in LaTeX/Beamer output.

Close #6107.

1 files changed, 27 insertions, 0 deletions

diff --git a/test/command/6107.md b/test/command/6107.md
new file mode 100644
index 000000000..8444172ab
--- /dev/null
+++ b/test/command/6107.md
@@ -0,0 +1,27 @@
+```
+% pandoc -t beamer
+---
+title: A silly slide
+subtitle: Look for the sequel!
+---
+
+# A circus!
+
+## Another silly title
+
+Not much to do about nothing.
+
+## Epilogue {.standout}
+^D
+\hypertarget{a-circus}{%
+\section{A circus!}\label{a-circus}}
+
+\begin{frame}{Another silly title}
+\protect\hypertarget{another-silly-title}{}
+Not much to do about nothing.
+\end{frame}
+
+\begin{frame}[standout]{Epilogue}
+\protect\hypertarget{epilogue}{}
+\end{frame}
+```