bpo-34398: Allow glossary results to show up on search page (GH-8773)

diff --git a/Doc/conf.py b/Doc/conf.py
index 079d177..6b88c23 100644
--- a/Doc/conf.py
+++ b/Doc/conf.py
@@ -15,8 +15,7 @@
 
 extensions = ['sphinx.ext.coverage', 'sphinx.ext.doctest',
               'pyspecific', 'c_annotations', 'escape4chm',
-              'asdl_highlight', 'peg_highlight']
-
+              'asdl_highlight', 'peg_highlight', 'glossary_search']
 
 doctest_global_setup = '''
 try: