reactjsperformancesafari

What causes this warning on Safari? "This webpage is using significant energy. Closing it may improve the responsiveness of your Mac"


We have a React website running with lots of high-quality images that has been experiencing this warning. How do you begin debugging this warning message on Safari? Is there specific things that cause this?

Safari warning


Solution

  • This message is caused by Safari watchdog process that monitors the Javascript scripts running on a page. It is there to notify the user when a script is utilizing too many resources. Your page when loaded on my computer raises the CPU utilization to 68 percent. Be weary of loops and custom render code.

    Notes for improvement:

    The number of images is not the issue. It is the number of SVG images(on load) and the scripts causing the issue.