regression/bug in graphics inclusion with double extension

[Norbert Preining]

Hi David,

I finally found the time looking into the regression, and it turned out
that a *simple* document (without grffile or grfext) worked till
2019-09-30 and broke afterwards:
	\documentclass{article}
	\usepackage{graphicx}
	\begin{document}
	Hello
	\includegraphics{{oma.foo}.png}
	\end{document}
Mind the addition braces.

This worked up to know, and Sphinx uses that for documentation building
of python modules (sphinxdoc).

I just tested with LaTeX 2e <2019-10-01> patch level 2 (TL updated)
and there it works again, while with pl1 and no pl, it doesn't.

Is this correct?

Thanks

Norbert

--
PREINING Norbert                               http://www.preining.info
Accelia Inc. + IFMGA ProGuide + TU Wien + JAIST + TeX Live + Debian Dev
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