Undefined method failValidationErrors (PHP version 8.0.5)

CodeIgniter v4.2.0 works with PHP 7.4 or later.
See https://codeigniter4.github.io/CodeIgnit...highlights

P.S. I cannot see the images.

Since the images cannot load, I updated it to google drive links.
Anyway, I just updated my PHP version for it to work. Still, some may find this useful if there's a solution other than upgrading the PHP version.