diff --git a/doc/requirements.txt b/doc/requirements.txt
index f27bf9293..c6883a919 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,8 +1,5 @@
-# The order of packages is significant, because pip processes them in the order
-# of appearance. Changing the order has an impact on the overall integration
-# process, which may cause wedges in the gate later.
-
 reno>=3.4.0 # Apache-2.0
+sphinx-copybutton # MIT
+sphinx-substitution-extensions # MIT
 sphinx>=4.2.0 # BSD
 sphinxcontrib-svg2pdfconverter>=0.1.0 # BSD
-Sphinx-Substitution-Extensions # Apache-2.0
diff --git a/doc/source/conf.py b/doc/source/conf.py
index aa1b082c4..172201559 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -57,6 +57,7 @@
     'sphinx.ext.extlinks',
     #'sphinx.ext.intersphinx',
     'sphinxcontrib.rsvgconverter',
+    'sphinx_copybutton',
     'sphinx_substitution_extensions',
 ]