Dear Maintainer,

If the PROJECT_NUMBER tag is set to a non-empty value in the Doxygen
configuration file (Doxyfile), it is supposed to be rendered below the
PROJECT_NAME tag value on the title page of the LaTeX output (and on pdf files
generated from the LaTeX output).  However, a regression was introduced in
Doxygen 1.9.4 which resulted in the PROJECT_NUMBER tag value being omitted from
the LaTeX output.  See upstream bug report:
<https://github.com/doxygen/doxygen/issues/9367>

This was fixed in Doxygen 1.9.4 by upstream commit
b293309a4cacf4e6385a9a992165f6c30a0575ce. See:
<https://github.com/doxygen/doxygen/pull/9369/commits/b293309a4cacf4e6385a9a992165f6c30a0575ce>

The patch appears to apply cleanly to the 1.9.4-4 source, so I request it be
included in a future revision of the package.  (It is already fixed in the
"unstable" 1.9.8 package.)

To test:

1. Run `doxygen -u` in an empty directory.
2. Edit the Doxyfile and set a non-empty value for PROJECT_NUMBER.
3. Run `doxygen` to generate html and latex output in subdirectories of the
same names.
4. Examine the latex/refman.tex file and look for the `\begin{titlepage}`
environment and the `\begin{center}` environment therein. The value of the
PROJECT_NUMBER tag value (if non-empty) should appear somewhere between the
PROJECT_NAME tag value (which defaults to "My Project") and the "Generated by
Doxygen 1.9.4" text.
5. Optionally, if pdflatex and make are available, PDF output can be generated
as refman.pdf by running `make` in the latex subdirectory. On viewing the PDF
file, the PROJECT_NUMBER tag value (if non-empty) should appear between the
PROJECT NAME tag value line and the "Generated by Doxygen 1.9.4" line on the
title page.

If the bug is present, the non-empty PROJECT_NUMBER tag value is missing from
the refman.tex (step 4 above) and refman.pdf (step 5 above) files.

If the bug is fixed, the non-empty PROJECT_NUMBER tag value should appear as
described in refman.tex (step 4 above) and refman.pdf (step 5 above).