colors defined by xcolor[dvipsnames] not working

[vliegeois]

Since version 61684 (3.65), there is compilation error with pdflatex for beamer slides.
Any color defined in xcolor with dvipsnames: \documentclass[12pt,xcolor={dvipsnames}]{beamer}
is not recognized.
For instance, when using ForestGreen color with \textcolor{ForestGreen}{example} failed with error:

! Package xcolor Error: Undefined color `ForestGreen'.

This was fine with beamer 60801 (3.64).
I don't have the issue with beamerarticle:

\documentclass[12pt,a4paper,dvipsnames]{article}
\usepackage{beamerarticle}

Here is a minimal example:

\documentclass[11pt,mathserif,xcolor=dvipsnames]{beamer}
%\documentclass[12pt,a4paper,dvipsnames]{article}
%\usepackage{beamerarticle}
\mode<beamer>{%
\usetheme[hideothersubsections,
right,width=1mm]{Goettingen}
\useoutertheme{infolines}
}
\usepackage[utf8]{inputenc}
\title{Title}
\author{Vincent LIEGEOIS}
\date{\today}
\begin{document}
\mode<article>{\maketitle}
\mode<article>{\tableofcontents}
\begin{frame}
\titlepage
\end{frame}
\begin{frame}
  \frametitle{Bug report}
This is a small \textcolor{ForestGreen}{example}.
\end{frame}
\end{document}

Best regards

Vincent

[samcarter]

@vliegeois Sorry for that! I broke that when adding more flexible aspect ratios. As a temporary fix

\RequirePackage[dvipsnames]{xcolor}

\documentclass[11pt]{beamer}

\begin{document}

\begin{frame}
\frametitle{Bug report}
This is a small \textcolor{ForestGreen}{example}.
\end{frame}
\end{document}

[vliegeois]

@vliegeois Just curious: why do you have all these \mode without actually specifying a mode?

Which \mode are you referring at? I use \mode

to make the title and the table of content when using beamerarticle but not in beamer mode.

Thanks for the fix.
So I can remove this fix when beamer 3.66 will be available?

Thank you for the very quick reply :-)
Regards
Vincent

[samcarter]

Sorry about the comment about \mode. Before I applied code markup to your post, I could not see them. This is what your post looked like for me:

[samcarter]

Thanks for the fix.
So I can remove this fix when beamer 3.66 will be available?

I hope so :) I just asked @josephwright if he can release a new version

[vliegeois]

Indeed, there is an issue with markdown and < and > :-)

[samcarter]

@vliegeois If the code is not in a code block, I think they are interpreted as html tag thingies

[samcarter]

@vliegeois Oh, and instead of the mathserif option, better use \usefonttheme[onlymath]{serif} in your preamble

[vliegeois]

Thanks for the tip

[samcarter]

@vliegeois You're welcome!