Don't update metadata panel on thread opening

boards/static/js/thread_update.js

@@ -87,12 +87,14 b' function getThreadDiff() {'
     $.getJSON(diffUrl)
         .success(function(data) {
             var addedPosts = data.added;
+            var hasMetaUpdates = false;
 
             for (var i = 0; i < addedPosts.length; i++) {
                 var postText = addedPosts[i];
                 var post = $(postText);
 
-                updatePost(post)
+                updatePost(post);
+                hasMetaUpdates = true;
             }
 
             var updatedPosts = data.updated;
@@ -101,10 +103,13 b' function getThreadDiff() {'
                 var postText = updatedPosts[i];
                 var post = $(postText);
 
-                updatePost(post)
+                updatePost(post);
+                hasMetaUpdates = true;
             }
 
-            updateMetadataPanel();
+            if (hasMetaUpdates) {
+                updateMetadataPanel();
+            }
 
             // TODO Process removed posts if any
             $('.metapanel').attr('data-last-update', data.last_update);