diff --git a/requirements.txt b/requirements.txt
index ad7e55c6d..4d7767a79 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,8 @@
+docutils==0.16.0  # Compatibility with sphinx-tabs 3.2.0.
 jinja2<3.1  # Compatibility with Sphinx 3.5.4.
 pygments~=2.6.1
 pygments-csv-lexer~=0.1
 pysass~=0.1.0
 sphinx~=3.0
+sphinx-tabs==3.2.0
 werkzeug==0.14.1