diff --git a/docs/requirements.txt b/docs/requirements.txt
index d5f1c66..41db998 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,2 +1,6 @@
-sphinx
-sphinx-rtd-theme==0.4.3
\ No newline at end of file
+sphinx<=3.4.3
+sphinx-rtd-theme==0.4.3
+sphinxemoji>=0.1.8
+sphinx-copybutton>=0.3.1
+docutils<0.18
+Jinja2<3.1