diff --git a/jupyter_notebook/static/notebook/less/completer.less b/jupyter_notebook/static/notebook/less/completer.less
index c6f64efb7..03f0fe470 100644
--- a/jupyter_notebook/static/notebook/less/completer.less
+++ b/jupyter_notebook/static/notebook/less/completer.less
@@ -5,6 +5,7 @@
     border: 1px solid @border_color;
     .corner-all;
     .box-shadow(0px 6px 10px -1px #adadad);
+    line-height: 1;
 }
 
 .completions select {