failed to generate epub file on release/2.3 branch

[snikulov]

Unable to generate epub from documentation for release/2.3 branch
Error as follows

╭─snikulov@snikulov-home ~/work/github/docs ‹release/2.3› 
╰─$ make epub         
sphinx-build -b epub -d _build/doctrees   . _build/epub
Running Sphinx v7.2.6
/usr/lib/python3.12/site-packages/sphinxcontrib/applehelp/__init__.py:24: RemovedInSphinx80Warning: The alias 'sphinx.util.SkipProgressMessage' is deprecated, use 'sphinx.util.display.SkipProgressMessage' instead. Check CHANGES for Sphinx API modifications.
  from sphinx.util import SkipProgressMessage, progress_message
/usr/lib/python3.12/site-packages/sphinxcontrib/applehelp/__init__.py:24: RemovedInSphinx80Warning: The alias 'sphinx.util.progress_message' is deprecated, use 'sphinx.util.display.progress_message' instead. Check CHANGES for Sphinx API modifications.
  from sphinx.util import SkipProgressMessage, progress_message
/usr/lib/python3.12/site-packages/sphinxcontrib/htmlhelp/__init__.py:26: RemovedInSphinx80Warning: The alias 'sphinx.util.progress_message' is deprecated, use 'sphinx.util.display.progress_message' instead. Check CHANGES for Sphinx API modifications.
  from sphinx.util import progress_message
Initializing Spelling Checker 8.0.0
building [mo]: targets for 0 po files that are out of date
writing output... 
building [epub]: targets for 292 source files that are out of date
updating environment: [new config] 292 added, 0 changed, 0 removed
direct use of the spelling directive is deprecated, replace ".. spelling::" with ".. spelling:word-list::"
reading sources... [100%] whatsnew
looking for now-outdated files... none found
pickling environment... done
checking consistency... done
preparing documents... done
copying assets... copying static files... done
copying extra files... done
done
/home/snikulov/work/github/docs/devops/versioning/resolve_prereleases.rst:33: WARNING: unknown node type: <graphviz: >
sphinx-sitemap: sitemap.xml was generated for URL https://docs.conan.io/ in /home/snikulov/work/github/docs/_build/epub/sitemap.xml

Exception occurred:
  File "/home/snikulov/.local/lib/python3.12/site-packages/docutils/nodes.py", line 2041, in unknown_departure
    raise NotImplementedError(
NotImplementedError: <class 'sphinx.writers.html5.HTML5Translator'> departing unknown node type: graphviz
The full traceback has been saved in /tmp/sphinx-err-_8v2s80i.log, if you want to report the issue to the developers.
Please also report this if it was a user error, so that a better error message can be provided next time.
A bug report can be filed in the tracker at <https://github.com/sphinx-doc/sphinx/issues>. Thanks!
make: *** [Makefile:123: epub] Error 2
╭─snikulov@snikulov-home ~/work/github/docs ‹release/2.3› 

[memsharded]

Thanks for reporting @snikulov

I have been able to reproduce, it seems the current setup doesn't support the epub building.

Maybe @RubenRBS might know a bit better about this.