Because macOS 10.15.7 (Catalina) no longer supports native WhatsApp desktop applications, utilizing WhatsApp Web
Using is a seamless way to manage your conversations without constantly picking up your phone. While Apple has moved far beyond Catalina (which is from 2019/2020), this legacy operating system still supports modern web browsers, making it easy to access WhatsApp's desktop functionalities. whatsapp web mac os 10157 link
If you encounter any issues while using WhatsApp Web on Mac OS, here are some troubleshooting tips: Because macOS 10