Hello @msyahrizan,
From Media >> Stateless Settings (page) >> Settings tab >> Cache-Control entry.
The default value is public, max-age=36000, must-revalidate. Change the max-age to what you need, max-age is in second.
For more info search google with Cache Control header.
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control
What your recommendation for Gtmetrix not asking me to add expires headers (There is 1 static component without a far-future expiration date.)
I already put this on the box, but still not work
public, max-age=31536000, must-revalidate
@msyahrizan
For new images it will work as expected.
For existing image you have to sync the images from Sync tab of Stateless Settings page.