How to change the Cat Image from 404 Not Found Page
You can change the image by replacing the existing one in templates/system/modules/error/themes/base/img/page-not-found.png.
Then, you will have to clear the static cache from the admin panel (Admin Panel, -> Tool -> Caches -> Caches Manager).
Finally, you might also have to clear your browser's cache if it still caches the previous image.
Done! 😃
