diff --git a/core/main.js b/core/main.js
index 0d75c299..a0ee4f06 100644
--- a/core/main.js
+++ b/core/main.js
@@ -75,8 +75,6 @@ main._showReleaseNotes = function (details) {
             [Setting.LAST_MAPPING_UPDATE]: lastMappingUpdate
         }, function() {
 
-            previousVersion = details.previousVersion;
-
             if (details.temporary !== true) {
 
                 chrome.storage.sync.get([Setting.HIDE_RELEASE_NOTES], function (items) {