diff --git a/doc/requirements.txt b/doc/requirements.txt
index 36adfde..b6b324f 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -3,4 +3,4 @@ sphinxcontrib-programoutput
 sphinx-autodoc-typehints
 reno>=2.8.0 # Apache-2.0
 zuul-sphinx
-sphinx_rtd_theme
+sphinx_rtd_theme>=1.2.2