You should really redirect before you start page output
  • line 1144 of /lib/outputrenderers.php: call to debugging()
  • line 2869 of /lib/weblib.php: call to core_renderer->redirect_message()
  • line 36 of /course/format/topics/format.php: call to redirect()
  • line 280 of /course/view.php: call to require()