diff --git a/src/app/display-buffer.coffee b/src/app/display-buffer.coffee
index d35e31f1e..546f7ee7d 100644
--- a/src/app/display-buffer.coffee
+++ b/src/app/display-buffer.coffee
@@ -13,6 +13,7 @@ Subscriber = require 'subscriber'
 module.exports =
 class DisplayBuffer
   @idCounter: 1
+  screenLines: null
   rowMap: null
   tokenizedBuffer: null
   markers: null