We'll create fresh WordPress site with QRCode installed. You have 20 minutes to test the plugin after that site we'll be deleted.
Generate QR Code by shortcode. Inline base64 SVG image. No extra image file generated. Local generator, no need online Google service.
Use [qrcode]Example string[/qrcode]
to generate the QR Code.
Use [qrcode size=10 margin=5]Example string[/qrcode]
to set size/margin. Default size=3, margin=3.