diff --git a/stylesheets/_session_left_pane.scss b/stylesheets/_session_left_pane.scss
index 8c0c4a48c..b45426787 100644
--- a/stylesheets/_session_left_pane.scss
+++ b/stylesheets/_session_left_pane.scss
@@ -535,6 +535,7 @@ $session-compose-margin: 20px;
   &-section {
     display: flex;
     flex-direction: column;
+    flex: 1;
   }
 
   &-category-list-item {