Fix Thread Stats slowdown; use querySelector once.

4chan_x.user.js

@@ -2275,6 +2275,8 @@
         left: '0px'
       }, html);
       dialog.className = 'dialog';
+      threadStats.postcountID = $('#postcount', dialog);
+      threadStats.imagecountID = $('#imagecount', dialog);
       $.append(d.body, dialog);
       return g.callbacks.push(threadStats.node);
     },
@@ -2282,15 +2284,13 @@
       if (root.className) {
         return;
       }
-      threadStats.posts++;
+      threadStats.postcountID.textContent = ++threadStats.posts;
       if ($('img[md5]', root)) {
-        threadStats.images++;
+        threadStats.imagecountID.textContent = ++threadStats.images;
         if (threadStats.images > 150) {
-          $('#imagecount').className = 'error';
+          return threadStats.imagecountID.className = 'error';
         }
       }
-      $('#postcount').textContent = threadStats.posts;
-      return $('#imagecount').textContent = threadStats.images;
     }
   };
   unread = {

changelog

@@ -1,5 +1,6 @@
 - mayhem:
   - Fix Auto Watch Reply and prevent upload of too large files when auto posting
+  - Thread Stats performance fix, especially on long threads
 
 2.15.1
 - mayhem:

script.coffee

@@ -1746,17 +1746,17 @@ threadStats =
     html = "<div class=move><span id=postcount>#{threadStats.posts}</span> / <span id=imagecount>#{threadStats.images}</span></div>"
     dialog = ui.dialog 'stats', bottom: '0px', left: '0px', html
     dialog.className = 'dialog'
+    threadStats.postcountID  = $ '#postcount',  dialog
+    threadStats.imagecountID = $ '#imagecount', dialog
     $.append d.body, dialog
     g.callbacks.push threadStats.node
   node: (root) ->
     return if root.className
-    threadStats.posts++
+    threadStats.postcountID.textContent = ++threadStats.posts
     if $ 'img[md5]', root
-      threadStats.images++
+      threadStats.imagecountID.textContent = ++threadStats.images
       if threadStats.images > 150
-        $('#imagecount').className = 'error'
+        threadStats.imagecountID.className = 'error'
-    $('#postcount').textContent = threadStats.posts
-    $('#imagecount').textContent = threadStats.images
 
 unread =
   init: ->