diff --git a/requirements.txt b/requirements.txt
index e90cd12..3962c70 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -27,7 +27,7 @@ Flask-WTF==0.14.2
 future==0.18.1
 guacamole==0.9.2
 h5py==2.10.0
-html5lib==0.999
+html5lib==0.999999999
 httplib2==0.9.1
 idna==2.0
 importlib-metadata==0.23