chunk notice

--- a/src/Controller/Chan.php
+++ b/src/Controller/Chan.php
@@ -492,6 +492,11 @@ class Chan extends Common
 
             // get the current status of the thread
             $thread_status = $board->getThreadStatus();
+
+            if(!isset($options['type']) && $thread_status['nreplies'] > 5000) {
+                return $this->error(_i('Threads this large can\'t be opened reliably. <a href="'.$this->uri->create($this->radix->shortname.'/chunk/'.$num.'/').'">Use the chunked method</a> or <a href="'.$this->uri->create($this->radix->shortname.'/last/50/'.$num.'/').'">view last 50 posts</a>.'));
+            }
+
             $last_modified = $thread_status['last_modified'];
 
             $this->setLastModified($last_modified);