: This creates an icon in your Dock that opens WhatsApp in its own window, mimicking the feel of a native application. About supported operating systems | WhatsApp Help Center
This forces the WhatsApp server to send you the lightweight, JavaScript-based client rather than the heavy WebKit/Blink optimized version. It is not permanent—you must repeat this every session—but it works for quick logins. whatsapp web mac os 10.15.7