diff --git a/dev_server/requirements.txt b/dev_server/requirements.txt
index 0b26095..2b7d000 100644
--- a/dev_server/requirements.txt
+++ b/dev_server/requirements.txt
@@ -32,7 +32,7 @@ jupytext==1.2.4
 kiwisolver==1.1.0
 MarkupSafe==1.1.1
 matplotlib==3.1.1
-mistune==0.8.4
+mistune==2.0.3
 more-itertools==7.2.0
 msgpack==0.6.2
 nbconvert==5.6.0