We'll create fresh WordPress site with QR Block installed. You have 20 minutes to test the plugin after that site we'll be deleted.
The QR Block plugin provides a few blocks:
Also, it renders the QR code of the current post in the Post sidebar. A simple but functional way o load the post on mobile, for instance.
You can follow development, file an issue, suggest features, and view the source at the Github WPHackers/qr-block repo.
This block is powered by the brilliant qrcode.react library.