diff --git a/docs/requirements.txt b/docs/requirements.txt
index f90e0a454..5f13ef308 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,7 +1,7 @@
 # requirements to build documentation
 Sphinx<2.0
 sphinxcontrib-issuetracker
-alabaster
+alabaster==0.7.16
 doc8
 eve
 jinja2<3.1.0