Running on the latest version of zencart, and would like to know what people have found to be the best way of using defer & async for javascript, and also lazyloading images, to help with page speed.

There are some older plugins for lazy loading, which haven't been updated for a while, so would not want to go down that route of using outdated stuff.

There is also this plugin:

https://www.zen-cart.com/downloads.php?do=file&id=1774

Has anyone had any success with the above plugin?

Kind Regards,

Andy