Target slower devices

Your computer is likely faster than what players of your games are using, especially if they are on mobile devices like smartphones and tablets. As you add more and more features to your game over time, it is likely going to require more CPU. It is therefore useful to enable CPU throttling when testing your game to ensure that it runs smoothly even on slower devices.

In Chrome Dev Tools, go to Performance, then expand using the cog wheel on the right to show the CPU throttle options. The amount that is useful to throttle will depend on your own device so it can be best to re-calibrate so you can select a mid or low-tier mobile setting.