/captcha/png/QS1TN4K1S0W9X4FFF1N3
  (8) Trying to get property of non-object   CaptchaController.php   line 49     17-8-18   15:00
FrontController->dispatch() # line   18, file: /home/arfooo/www/index.php
  call_user_func_array(Array[2], Array[1]) # line  211, file: /home/arfooo/www/core/FrontController.php
    CaptchaController->pngAction("QS1TN4K1S0W9X4FFF1N3") # line    0, file: unknown