diff --git a/doc/utils/sphinx-config/conf.py.in b/doc/utils/sphinx-config/conf.py.in
index 17cb3c2395..baf472b9f9 100644
--- a/doc/utils/sphinx-config/conf.py.in
+++ b/doc/utils/sphinx-config/conf.py.in
@@ -241,7 +241,7 @@ html_show_sourcelink = False
 # Output file base name for HTML help builder.
 htmlhelp_basename = 'LAMMPSdoc'
 
-html_add_permalinks = ''
+html_permalinks = True
 
 if 'epub' in sys.argv:
   html_math_renderer = 'imgmath'