diff --git a/CHANGELOG.md b/CHANGELOG.md
index 773f836d6..2cbe9636d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
+## 3.16.0 - *2014-01-30*
+
 - More index navigation improvements:
- - New index mode: `catalog`
+ - New index mode: `catalog`<br>
+  ![catalog mode](img/changelog/3.16.0/0.png)
  - When in catalog mode, use `Shift+Click` to hide, and `Alt+Click` to pin threads.
  - Existing features affect the catalog mode such as:
  <ul>
diff --git a/img/changelog/3.16.0/0.png b/img/changelog/3.16.0/0.png
new file mode 100644
index 000000000..c7fe125f4
Binary files /dev/null and b/img/changelog/3.16.0/0.png differ
diff --git a/lib/$.coffee b/lib/$.coffee
index 78e8f54f7..b2029d711 100644
--- a/lib/$.coffee
+++ b/lib/$.coffee
@@ -267,7 +267,6 @@ $.set = do ->
   setArea = (area) ->
     data = items[area]
     return if !Object.keys(data).length or timeout[area]
-    items[area] = {}
     chrome.storage[area].set data, ->
       if chrome.runtime.lastError
         c.error chrome.runtime.lastError.message
@@ -276,23 +275,20 @@ $.set = do ->
         timeout[area] = setTimeout setArea, $.MINUTE, area
         return
       delete timeout[area]
+    items[area] = {}
 
-  setAll = $.debounce $.SECOND, ->
-    for key in $.localKeys
-      if key of items.sync
-        items.local[key] = items.sync[key]
-        delete items.sync[key]
-    try
-      setArea 'local'
-      setArea 'sync'
-    catch err
-      c.error err.stack
+  setAll = $.debounce 5 * $.SECOND, ->
+    setArea 'local'
+    setArea 'sync'
 
   (key, val) ->
     if typeof key is 'string'
       items.sync[key] = val
     else
       $.extend items.sync, key
+    for key in $.localKeys when key of items.sync
+      items.local[key] = items.sync[key]
+      delete items.sync[key]
     setAll()
 $.clear = (cb) ->
   count = 2
diff --git a/package.json b/package.json
index 7c43bca47..43bb3ffb7 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "4chan-X",
-  "version": "3.15.2",
+  "version": "3.16.0",
   "description": "Cross-browser extension for productive lurking on 4chan.",
   "meta": {
     "name": "4chan X",
@@ -26,13 +26,13 @@
     "grunt-bump": "~0.0.13",
     "grunt-concurrent": "~0.4.3",
     "grunt-contrib-clean": "~0.5.0",
-    "grunt-contrib-coffee": "~0.8.2",
+    "grunt-contrib-coffee": "~0.9.0",
     "grunt-contrib-compress": "~0.6.0",
     "grunt-contrib-concat": "~0.3.0",
     "grunt-contrib-copy": "~0.5.0",
     "grunt-contrib-watch": "~0.5.3",
     "grunt-shell": "~0.6.4",
-    "load-grunt-tasks": "~0.2.1"
+    "load-grunt-tasks": "~0.3.0"
   },
   "repository": {
     "type": "git",
diff --git a/src/Filtering/ThreadHiding.coffee b/src/Filtering/ThreadHiding.coffee
index 03d8ae635..5aead17aa 100644
--- a/src/Filtering/ThreadHiding.coffee
+++ b/src/Filtering/ThreadHiding.coffee
@@ -19,7 +19,7 @@ ThreadHiding =
       thread = Get.threadFromRoot root
       continue unless thread.isHidden
       unless thread.stub
-        nodes[i + 1].hidden = true
+        Index.nodes[i + 1].hidden = true
       else unless root.contains thread.stub
         # When we come back to a page, the stub is already there.
         ThreadHiding.makeStub thread, root
diff --git a/src/General/Build.coffee b/src/General/Build.coffee
index 1a3efa7ed..f342857af 100644
--- a/src/General/Build.coffee
+++ b/src/General/Build.coffee
@@ -176,7 +176,7 @@ Build =
       ''
 
     if isOP and g.VIEW is 'index'
-      pageNum   = Math.floor Index.liveThreadIDs.indexOf(postID) / Index.threadsNumPerPage
+      pageNum   = Index.liveThreadIDs.indexOf(postID) // Index.threadsNumPerPage
       pageIcon  = " <span class=page-num title='This thread is on page #{pageNum} in the original index.'>Page #{pageNum}</span>"
       replyLink = " &nbsp; <span>[<a href='/#{boardID}/res/#{threadID}' class=replylink>Reply</a>]</span>"
     else
@@ -284,7 +284,7 @@ Build =
 
     postCount = data.replies + 1
     fileCount = data.images  + !!data.ext
-    pageCount = Math.floor Index.liveThreadIDs.indexOf(thread.ID) / Index.threadsNumPerPage
+    pageCount = Index.liveThreadIDs.indexOf(thread.ID) // Index.threadsNumPerPage
 
     subject = if thread.OP.info.subject
       "<div class='subject'>#{thread.OP.info.subject}</div>"
diff --git a/src/General/CatalogThread.coffee b/src/General/CatalogThread.coffee
index ae8f832d0..a7bebe7bc 100644
--- a/src/General/CatalogThread.coffee
+++ b/src/General/CatalogThread.coffee
@@ -7,8 +7,9 @@ class CatalogThread
     @board = @thread.board
     @nodes =
       root: root
-      thumb:     $ '.thumb',      root
-      postCount: $ '.post-count', root
-      fileCount: $ '.file-count', root
-      pageCount: $ '.page-count', root
+      thumb:     $ '.thumb',        root
+      icons:     $ '.thread-icons', root
+      postCount: $ '.post-count',   root
+      fileCount: $ '.file-count',   root
+      pageCount: $ '.page-count',   root
     @thread.catalogView = @
diff --git a/src/General/DataBoard.coffee b/src/General/DataBoard.coffee
index dc4319816..2aab44b17 100644
--- a/src/General/DataBoard.coffee
+++ b/src/General/DataBoard.coffee
@@ -71,7 +71,7 @@ class DataBoard
   ajaxClean: (boardID) ->
     $.cache "//a.4cdn.org/#{boardID}/threads.json", (e) =>
       if e.target.status isnt 200
-        @delete boardID if e.target.status is 404
+        @delete {boardID} if e.target.status is 404
         return
       board   = @data.boards[boardID]
       threads = {}
diff --git a/src/General/Get.coffee b/src/General/Get.coffee
index 9fe328a13..d05651789 100644
--- a/src/General/Get.coffee
+++ b/src/General/Get.coffee
@@ -188,7 +188,7 @@ Get =
 
     comment = bq.innerHTML
       # greentext
-      .replace(/(^|>)(&gt;[^<$]*)(<|$)/g, '$1<span class=quote>$2</span>$3')
+      .replace /(^|>)(&gt;[^<$]*)(<|$)/g, '$1<span class=quote>$2</span>$3'
       # quotes
       .replace /((&gt;){2}(&gt;\/[a-z\d]+\/)?\d+)/g, '<span class=deadlink>$1</span>'
 
diff --git a/src/General/Index.coffee b/src/General/Index.coffee
index 76eaf45e1..7b4f9d8ae 100644
--- a/src/General/Index.coffee
+++ b/src/General/Index.coffee
@@ -353,7 +353,7 @@ Index =
       threadRoot = Build.thread g.BOARD, threadData
       Index.nodes.push threadRoot, $.el 'hr'
       if thread = g.BOARD.threads[threadData.no]
-        thread.setPage Math.floor i / Index.threadsNumPerPage
+        thread.setPage i // Index.threadsNumPerPage
         thread.setCount 'post', threadData.replies + 1,                threadData.bumplimit
         thread.setCount 'file', threadData.images  + !!threadData.ext, threadData.imagelimit
         thread.setStatus 'Sticky', !!threadData.sticky
@@ -403,8 +403,8 @@ Index =
     Main.callbackNodes Post, posts
   buildCatalogViews: ->
     threads = Index.sortedNodes
-      .filter((n, i) -> !(i % 2))
-      .map((threadRoot) -> Get.threadFromRoot threadRoot)
+      .filter (n, i) -> !(i % 2)
+      .map (threadRoot) -> Get.threadFromRoot threadRoot
       .filter (thread) -> !thread.isHidden
     catalogThreads = []
     for thread in threads when !thread.catalogView
@@ -417,8 +417,8 @@ Index =
         sortedThreadIDs = Index.liveThreadIDs
       when 'lastreply'
         sortedThreadIDs = [Index.liveThreadData...].sort((a, b) ->
-          a = a.last_replies[a.last_replies.length - 1] if 'last_replies' of a
-          b = b.last_replies[b.last_replies.length - 1] if 'last_replies' of b
+          [..., a] = a.last_replies if 'last_replies' of a
+          [..., b] = b.last_replies if 'last_replies' of b
           b.no - a.no
         ).map (data) -> data.no
       when 'birth'
diff --git a/src/General/Thread.coffee b/src/General/Thread.coffee
index 81acfc439..8a9df031f 100644
--- a/src/General/Thread.coffee
+++ b/src/General/Thread.coffee
@@ -33,7 +33,7 @@ class Thread
     typeLC = type.toLowerCase()
     unless status
       $.rm $ ".#{typeLC}Icon", @OP.nodes.info
-      $.rm $ ".#{typeLC}Icon", @catalogView if @catalogView
+      $.rm $ ".#{typeLC}Icon", @catalogView.nodes.icons if @catalogView
       return
 
     icon = $.el 'img',
@@ -49,8 +49,7 @@ class Thread
     $.after root, [$.tn(' '), icon]
 
     return unless @catalogView
-    root = $ '.thread-icons', @catalogView
-    (if type is 'Sticky' and @isClosed then $.prepend else $.add) root, icon.cloneNode()
+    (if type is 'Sticky' and @isClosed then $.prepend else $.add) @catalogView.nodes.icons, icon.cloneNode()
 
   pin: ->
     @isOnTop = @isPinned = true
diff --git a/src/General/UI.coffee b/src/General/UI.coffee
index e52774aea..ee852ccd4 100644
--- a/src/General/UI.coffee
+++ b/src/General/UI.coffee
@@ -191,7 +191,7 @@ UI = do ->
     # prevent text selection
     e.preventDefault()
     if isTouching = e.type is 'touchstart'
-      e = e.changedTouches[e.changedTouches.length - 1]
+      [..., e] = e.changedTouches
     # distance from pointer to el edge is constant; calculate it here.
     el = $.x 'ancestor::div[contains(@class,"dialog")][1]', @
     rect = el.getBoundingClientRect()
diff --git a/src/Posting/QR.coffee b/src/Posting/QR.coffee
index 9b5f92aba..c68d7cab9 100644
--- a/src/Posting/QR.coffee
+++ b/src/Posting/QR.coffee
@@ -50,14 +50,13 @@ QR =
           else
             QR.status()
 
-    QR.persist() if Conf['Persistent QR']
+    return unless Conf['Persistent QR']
+    QR.open()
+    QR.hide() if Conf['Auto-Hide QR'] or g.VIEW is 'index' and Conf['Index Mode'] is 'catalog'
 
   node: ->
     $.on $('a[title="Quote this post"]', @nodes.info), 'click', QR.quote
 
-  persist: ->
-    QR.open()
-    QR.hide() if Conf['Auto-Hide QR']
   open: ->
     if QR.nodes
       QR.nodes.el.hidden = false
diff --git a/src/Posting/QR.cooldown.coffee b/src/Posting/QR.cooldown.coffee
index ce0fa7960..2c0c7a4e0 100644
--- a/src/Posting/QR.cooldown.coffee
+++ b/src/Posting/QR.cooldown.coffee
@@ -48,7 +48,7 @@ QR.cooldown =
       $.delete "cooldown.#{g.BOARD}"
   count: ->
     unless Object.keys(QR.cooldown.cooldowns).length
-      $.delete "#{g.BOARD}.cooldown"
+      $.delete "cooldown.#{g.BOARD}"
       delete QR.cooldown.isCounting
       delete QR.cooldown.seconds
       QR.status()
@@ -76,7 +76,7 @@ QR.cooldown =
       if isReply is cooldown.isReply
         # Only cooldowns relevant to this post can set the seconds variable:
         #   reply cooldown with a reply, thread cooldown with a thread
-        elapsed = Math.floor (now - start) / $.SECOND
+        elapsed = (now - start) // $.SECOND
         continue if elapsed < 0 # clock changed since then?
         type = unless isReply
           'thread'
@@ -91,7 +91,7 @@ QR.cooldown =
         seconds = Math.max seconds, types[type] - elapsed
 
     if seconds and Conf['Cooldown Prediction'] and hasFile and upSpd
-      seconds -= Math.floor post.file.size / upSpd * upSpdAccuracy
+      seconds -= post.file.size // (upSpd * upSpdAccuracy)
       seconds  = Math.max seconds, 0
     # Update the status when we change posting type.
     # Don't get stuck at some random number.
diff --git a/src/Posting/QR.post.coffee b/src/Posting/QR.post.coffee
index 06194bbe3..a38362840 100644
--- a/src/Posting/QR.post.coffee
+++ b/src/Posting/QR.post.coffee
@@ -35,7 +35,7 @@ QR.post = class
     else
       'new'
 
-    prev = QR.posts[QR.posts.length - 1]
+    [..., prev] = QR.posts
     QR.posts.push @
     @nodes.spoiler.checked = @spoiler = if prev and Conf['Remember Spoiler']
       prev.spoiler