Just found: W3.org now includes QR Codes in the Mobile Web compatibility test:

 ”Entering an address is a pain on a phone? Quite often, indeed, so a couple of alternatives to save you a bit of that pain:

if your phone has a camera and a QR code reader (which you can probably find out on your preferred search engine), you can point your camera’s phone to the following code, and it will open the right page in your browser:”