Missed one.

builds/4chan-X.user.js

@@ -4957,7 +4957,7 @@
       for (ID in _ref) {
         post = _ref[ID];
         if (post.cb) {
-          post.cb.call(post);
+          post.cb();
         }
       }
       return QuoteThreading.hasRun = true;

builds/crx/script.js

@@ -4960,7 +4960,7 @@
       for (ID in _ref) {
         post = _ref[ID];
         if (post.cb) {
-          post.cb.call(post);
+          post.cb();
         }
       }
       return QuoteThreading.hasRun = true;

src/Quotelinks/QuoteThreading.coffee

@@ -27,7 +27,7 @@ QuoteThreading =
   setup: ->
     $.off d, '4chanXInitFinished', QuoteThreading.setup
 
-    post.cb.call post for ID, post of g.posts when post.cb
+    post.cb() for ID, post of g.posts when post.cb
 
     QuoteThreading.hasRun = true