diff --git a/_sass/_sidebar.scss b/_sass/_sidebar.scss
index 3460b36b6d2d7..46e34257bfdd6 100644
--- a/_sass/_sidebar.scss
+++ b/_sass/_sidebar.scss
@@ -14,6 +14,8 @@
   margin-bottom: 1em;
 
   @media screen and (min-width: $sidebar-min-width) {
+    height: 100vh;
+    overflow-y: auto;               // Add scrollbar if the sidebar is too long
     position: fixed;
     padding-top: $masthead-height;
   }