I shall contact WhatsApp product support and see what they can do. Turning off desktop alerts and sounds in the client settings does not fix it however, so for the moment it doesn’t seem possible to prevent this system insomnia from occurring. I assume that this sleep issue is related to the notification feature of WhatsApp Web, since the assertion references Mac OS X’s coreaudiod process. With the WhatsApp Web session closed: $ /usr/bin/pmset -g assertions

Pid 346(coreaudiod): 00:00:50 PreventUserIdleSystemSleep named: '532.preventuseridlesleep' To do that, just navigate to the WhatsApp Web tab on the official WhatsApp website and repeat the steps above once again. Another way to use WhatsApp on Mac is through the browser. With the WhatsApp Web client running: $ /usr/bin/pmset -g assertions WhatsApp Desktop Mac app is also available through the official App Store, with all the installation steps being largely the same. Summarily, WhatsApp Web is a browser-based version of WhatsApp while WhatsApp Desktop is the WhatsApp app for. If you run the web client in a Google Chrome session on Mac OS X then a kernel assertion is established which prevents the system from sleeping, regardless of energy saver system preferences. WhatsApp Desktop is a standalone app that you can install on your Windows or Mac.

So far so good, but I have encountered one significant drawback.

It allows users to link their browser to their WhatsApp account and interact with chat sessions just like you do in the mobile app. The new WhatsApp Web client is a welcome companion to the hugely popular WhatsApp Messenger cross-platform mobile application.

Web whatsapp for mac