Note: Scanning a Twitter QR code will bring up the account’s profile, while scanning an external QR code will open a website or app.
What does an “invalid code” mean?
Only QR codes with links beginning with http:// or https:// can be scanned successfully. If you see an error message for a Twitter QR code, the code may no longer be valid if the account has changed their username.
Will my QR code change if I make updates to my Twitter profile?
If you change your profile image, the profile image displayed on the QR code will change. Any previous QR codes with the previous image will still be valid.
Changing your username however, will change the QR code completely and your previous code will be invalid.