Google has rolled back a recent release of its reCaptcha captcha script after a bug caused the service to no longer work on Firefox for Windows.

However, the reCAPTCHA API that supports the ReCAPTCHA checkbox is still working in the background. It allows Google to collect and analyze information about devices and apps.

NPR's Scott Simon speaks with Amanda Fennell, a cybersecurity expert, about CAPTCHA tests that verify if a website visitor is human or bot. They are getting harder.

Google engineers are working on an improved version of the reCAPTCHA system that uses a computer algorithm to distinguish between automated bots and real humans, and requires no user interaction ...