Probably the best free available solution to QRCodes in OpenCart 2/3 !

This package provides QR Code generating solution based on Google Infographic API:
The main features of this extension include:

• HTML5 rendered image in responsive OpenCart 2/3 themes - no need to edit the theme
  
• QR img tag src populated in a consistent way with the shop SSL configuration: uses HTTPS when enabled for the store and HTTP when disabled - no need to explain your customers why their browser throws at them security alerts
  
• accommodating custom port setup - working on http://my_shop:1234/my_product...
  
• QR img tag additionally populated with product brand and model for better SEO
  
• QR img tag anonymous crossorigin to avoid warnings in the web browser
  
• delivered on VQMod - no files overridden
  
• the latest Google Infographic API guidelines applied
  
• explicit UTF-8 URL encoding
  
• super easy installation and managing with VQMod from Extensions dashboard
  
• speed optimized
  
• automatic QR size
  
• great help for any printing scenario
  

DEMO 1
DEMO 2
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