diff --git a/notebook/static/notebook/less/codemirror.less b/notebook/static/notebook/less/codemirror.less
index 37ca1db75..8576bc4e5 100644
--- a/notebook/static/notebook/less/codemirror.less
+++ b/notebook/static/notebook/less/codemirror.less
@@ -52,3 +52,6 @@
     .border-radius(0)
 }
 
+.CodeMirror-cursor {
+    border-left: 1.2px solid black;
+}