diff -r 000000000000 -r 6474c204b198 addon-sdk/source/examples/annotator/data/editor/annotation-editor.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/addon-sdk/source/examples/annotator/data/editor/annotation-editor.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,23 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+On a return key, send the content of the textArea back to the add-on,
+and zero the textArea for the next time.
+*/
+
+var textArea = document.getElementById('annotation-box');
+
+textArea.onkeyup = function(event) {
+  if (event.keyCode == 13) {
+    self.postMessage(textArea.value);
+    textArea.value = '';
+  }
+};
+
+self.on('message', function() {
+  var textArea = document.getElementById('annotation-box');
+  textArea.value = '';
+  textArea.focus();
+});