Source: https://cobaltstrike.net/2022/03/11/whatsapp-introduces-new-security-feature-for-web-apps/
WhatsApp has partnered with Cloudfare to develop a Code Verify web extension.
The purpose of Code Verify is to confirm the integrity of the web application and make sure that there is no malicious code in it.
When using WhatsApp Web, the Code Verify extension creates a hash of the code received by the browser and compares it with the WhatsApp Web hash. If the code matches, the icon in the browser turns green. The red icon indicates that the code verification failed, and the orange one indicates that a possible risk or conflict with another extension has been detected.
After installation, the extension will start working automatically as soon as the user starts WhatsApp.
Code Verify is available for Google Chrome and Microsoft Edge, and will soon be available for Firefox.