This requirement will kick in the moment the system suspects suspicious activity. At that point, reCAPTCHA will forgo the old image puzzles and require you to scan a QR code with your smartphone to prove you’re human.
Any random QR code?
What if I don’t have a QR code available?
This sounds like an assumption that people will have something available that isn’t necessarily accurate a significant amount of the time.
I’d guess they want you to scan the QR code on your PC screen with your phone camera to verify your human identity. If you’re already browsing on your phone, your identity would already be linked through that, so no need to scan.
According to the support page (found here: https://support.google.com/recaptcha/answer/16609652) if you are browsing on a phone it will prompt you to click a link to open some kind of Captcha app on the device rather than scanning a QR code.
Any random QR code?
What if I don’t have a QR code available?
This sounds like an assumption that people will have something available that isn’t necessarily accurate a significant amount of the time.
I’d guess they want you to scan the QR code on your PC screen with your phone camera to verify your human identity. If you’re already browsing on your phone, your identity would already be linked through that, so no need to scan.
According to the support page (found here: https://support.google.com/recaptcha/answer/16609652) if you are browsing on a phone it will prompt you to click a link to open some kind of Captcha app on the device rather than scanning a QR code.