Switched it from using local storage to synced storage.

background.js

@@ -53,7 +53,7 @@ chrome.runtime.onMessage.addListener(function (request, sender, callback) {
 function getSponsorTimes(videoID, callback) {
   let sponsorTimes = [];
   let sponsorTimeKey = "sponsorTimes" + videoID;
-  chrome.storage.local.get([sponsorTimeKey], function(result) {
+  chrome.storage.sync.get([sponsorTimeKey], function(result) {
     let sponsorTimesStorage = result[sponsorTimeKey];
     if (sponsorTimesStorage != undefined && sponsorTimesStorage.length > 0) {
       sponsorTimes = sponsorTimesStorage;
@@ -79,7 +79,7 @@ function addSponsorTime(time) {
 
     //save this info
     let sponsorTimeKey = "sponsorTimes" + previousVideoID;
-    chrome.storage.local.set({[sponsorTimeKey]: sponsorTimes});
+    chrome.storage.sync.set({[sponsorTimeKey]: sponsorTimes});
   });
 }
 
@@ -109,7 +109,7 @@ function submitVote(type, UUID, callback) {
 function submitTimes(videoID, callback) {
   //get the video times from storage
   let sponsorTimeKey = 'sponsorTimes' + videoID;
-  chrome.storage.local.get([sponsorTimeKey], function(result) {
+  chrome.storage.sync.get([sponsorTimeKey], function(result) {
     let sponsorTimes = result[sponsorTimeKey];
 
     if (sponsorTimes != undefined && sponsorTimes.length > 0) {
@@ -140,7 +140,7 @@ function videoIDChange(currentVideoID) {
   if (previousVideoID != null) {
     //get the sponsor times from storage
     let sponsorTimeKey = 'sponsorTimes' + previousVideoID;
-    chrome.storage.local.get([sponsorTimeKey], function(result) {
+    chrome.storage.sync.get([sponsorTimeKey], function(result) {
       let sponsorTimes = result[sponsorTimeKey];
 
       if (sponsorTimes != undefined && sponsorTimes.length > 0) {
@@ -168,7 +168,7 @@ function getUserID(callback) {
   }
 
   //if it is not cached yet, grab it from storage
-  chrome.storage.local.get(["userID"], function(result) {
+  chrome.storage.sync.get(["userID"], function(result) {
     let userIDStorage = result.userID;
     if (userIDStorage != undefined) {
       userID = userIDStorage;
@@ -178,7 +178,7 @@ function getUserID(callback) {
       userID = generateUUID();
       
       //save this UUID
-      chrome.storage.local.set({"userID": userID});
+      chrome.storage.sync.set({"userID": userID});
 
       callback(userID);
     }

content.js

@@ -36,7 +36,7 @@ var hideVideoPlayerControls = false;
 //if the notice should not be shown
 //happens when the user click's the "Don't show notice again" button
 var dontShowNotice = false;
-chrome.storage.local.get(["dontShowNoticeAgain"], function(result) {
+chrome.storage.sync.get(["dontShowNoticeAgain"], function(result) {
   let dontShowNoticeAgain = result.dontShowNoticeAgain;
   if (dontShowNoticeAgain != undefined) {
     dontShowNotice = dontShowNoticeAgain;
@@ -106,7 +106,7 @@ function videoIDChange(id) {
   });
 
   //see if video control buttons should be added
-  chrome.storage.local.get(["hideVideoPlayerControls"], function(result) {
+  chrome.storage.sync.get(["hideVideoPlayerControls"], function(result) {
     if (result.hideVideoPlayerControls != undefined) {
       hideVideoPlayerControls = result.hideVideoPlayerControls;
     }
@@ -495,7 +495,7 @@ function closeAllSkipNotices(){
 }
 
 function dontShowNoticeAgain() {
-  chrome.storage.local.set({"dontShowNoticeAgain": true});
+  chrome.storage.sync.set({"dontShowNoticeAgain": true});
 
   dontShowNotice = true;
 
@@ -540,7 +540,7 @@ function submitSponsorTimes() {
 
         //clear the sponsor times
         let sponsorTimeKey = "sponsorTimes" + currentVideoID;
-        chrome.storage.local.set({[sponsorTimeKey]: []});
+        chrome.storage.sync.set({[sponsorTimeKey]: []});
       } else {
         //for a more detailed error message, they should check the popup
         //show that the upload failed

popup.js

@@ -22,7 +22,7 @@ var isYouTubeTab = false;
 
 //if the don't show notice again variable is true, an option to 
 //  disable should be available
-chrome.storage.local.get(["dontShowNoticeAgain"], function(result) {
+chrome.storage.sync.get(["dontShowNoticeAgain"], function(result) {
   let dontShowNoticeAgain = result.dontShowNoticeAgain;
   if (dontShowNoticeAgain != undefined && dontShowNoticeAgain) {
     document.getElementById("showNoticeAgain").style.display = "unset";
@@ -30,7 +30,7 @@ chrome.storage.local.get(["dontShowNoticeAgain"], function(result) {
 });
 
 //show proper video player controls option
-chrome.storage.local.get(["hideVideoPlayerControls"], function(result) {
+chrome.storage.sync.get(["hideVideoPlayerControls"], function(result) {
   let hideVideoPlayerControls = result.hideVideoPlayerControls;
   if (hideVideoPlayerControls != undefined && hideVideoPlayerControls) {
     document.getElementById("hideVideoPlayerControls").style.display = "none";
@@ -55,7 +55,7 @@ function loadTabData(tabs) {
 
   //load video times for this video 
   let sponsorTimeKey = "sponsorTimes" + currentVideoID;
-  chrome.storage.local.get([sponsorTimeKey], function(result) {
+  chrome.storage.sync.get([sponsorTimeKey], function(result) {
     let sponsorTimesStorage = result[sponsorTimeKey];
     if (sponsorTimesStorage != undefined && sponsorTimesStorage.length > 0) {
       if (sponsorTimesStorage[sponsorTimesStorage.length - 1] != undefined && sponsorTimesStorage[sponsorTimesStorage.length - 1].length < 2) {
@@ -140,7 +140,7 @@ chrome.runtime.onMessage.addListener(function (request, sender, callback) {
     sponsorTimes[sponsorTimesIndex][startTimeChosen ? 1 : 0] = request.time;
 
     let sponsorTimeKey = "sponsorTimes" + currentVideoID;
-    chrome.storage.local.set({[sponsorTimeKey]: sponsorTimes});
+    chrome.storage.sync.set({[sponsorTimeKey]: sponsorTimes});
 
     updateStartTimeChosen();
 
@@ -260,7 +260,7 @@ function clearTimes() {
   sponsorTimes = [];
 
   let sponsorTimeKey = "sponsorTimes" + currentVideoID;
-  chrome.storage.local.set({[sponsorTimeKey]: sponsorTimes});
+  chrome.storage.sync.set({[sponsorTimeKey]: sponsorTimes});
 
   displaySponsorTimes();
 
@@ -305,7 +305,7 @@ function submitTimes() {
 }
 
 function showNoticeAgain() {
-  chrome.storage.local.set({"dontShowNoticeAgain": false});
+  chrome.storage.sync.set({"dontShowNoticeAgain": false});
 
   chrome.tabs.query({
     active: true,
@@ -320,7 +320,7 @@ function showNoticeAgain() {
 }
 
 function hideVideoPlayerControls() {
-  chrome.storage.local.set({"hideVideoPlayerControls": true});
+  chrome.storage.sync.set({"hideVideoPlayerControls": true});
 
   chrome.tabs.query({
     active: true,
@@ -337,7 +337,7 @@ function hideVideoPlayerControls() {
 }
 
 function showVideoPlayerControls() {
-  chrome.storage.local.set({"hideVideoPlayerControls": false});
+  chrome.storage.sync.set({"hideVideoPlayerControls": false});
 
   chrome.tabs.query({
     active: true,