diff --git a/manpages/conf.py b/manpages/conf.py
index 7c3ea95..79e603b 100644
--- a/manpages/conf.py
+++ b/manpages/conf.py
@@ -1,25 +1,14 @@
 # Configuration file for the Sphinx documentation builder.
 #
-# This file only contains a selection of the most common options. For a full
-# list see the documentation:
+# For the full list of built-in configuration values, see the documentation:
 # https://www.sphinx-doc.org/en/master/usage/configuration.html
 
-# -- Path setup --------------------------------------------------------------
-
-# If extensions (or modules to document with autodoc) are in another directory,
-# add these directories to sys.path here. If the directory is relative to the
-# documentation root, use os.path.abspath to make it absolute, like shown here.
-#
-# import os
-# import sys
-# sys.path.insert(0, os.path.abspath('.'))
-
-
 # -- Project information -----------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
 
-project = u'NDN Essential Tools'
-copyright = u'Copyright © 2014-2022 Named Data Networking Project.'
-author = u'Named Data Networking Project'
+project = 'NDN Essential Tools'
+copyright = 'Copyright © 2014-2022 Named Data Networking Project.'
+author = 'Named Data Networking Project'
 
 # The short X.Y version.
 #version = ''
@@ -35,30 +24,18 @@
 
 
 # -- General configuration ---------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
 
-# If your documentation needs a minimal Sphinx version, state it here.
-#
-needs_sphinx = '1.3'
-
-# Add any Sphinx extension module names here, as strings. They can be
-# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
-# ones.
+needs_sphinx = '4.0'
 extensions = [
 ]
 
-# The master toctree document.
-master_doc = 'index'
-
-# Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']
-
-# List of patterns, relative to source directory, that match files and
-# directories to ignore when looking for source files.
-# This pattern also affects html_static_path and html_extra_path.
-exclude_patterns = ['Thumbs.db', '.DS_Store']
+exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
 
 
 # -- Options for manual page output ------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-manual-page-output
 
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
@@ -71,6 +48,3 @@
     ('ndndump',       'ndndump',       'traffic analysis tool',                      [], 8),
     ('ndn-dissect',   'ndn-dissect',   'NDN packet format inspector',                [], 1),
 ]
-
-# If true, show URL addresses after external links.
-#man_show_urls = True