I noticed that in my game the Pixi Application takes lot of CPU resources when it's running. Even when it's in background or is not visible, it consumes the CPU. Two Chrome processes are constantly using 25-30% CPU on my linux box (more on my macOS). It became very troublesome while working from a cafe on my macbook pro without charger. The app drained by battery in no time.
Only way to avoid this is to stop the pixi application ticker when you don't want it to consume resources. For a typical Pixi.js application, i.e. a game, it does make sense for the game to pause when it goes in background. Therefore I wrote this small routine using the `blur` event handler, to pause the Pixi app, whenever the window looses focus. This drops the CPU usage to 6-7% by Chrome processes.
In a browser or electron app, the window.onblur callback will get called whenever the focus switches from the app window to some other application (or even dev console). However in jsfiddle environment, you need to click on the application first and then click somewhere else for testing this functionality. That's because the code runs inside an iframe on jsfiddle page. The simple resume dialog lets you resume the app when you want.
You can try it here: https://jsfiddle.net/jay3sh/ft8am5fr/13/
If you have any other tips, or suggestions to reduce CPU usage, I would love to know.