diff --git a/doc/source/conf.py b/doc/source/conf.py
index 614e286d39..fe111bf222 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -64,6 +64,7 @@ pygments_style = 'sphinx'
 #html_theme_path = ["."]
 #html_theme = '_theme'
 #html_static_path = ['_static']
+html_theme_options = {'incubating': True}
 
 # Output file base name for HTML help builder.
 htmlhelp_basename = '%sdoc' % project