I needs to write the async or defer attributes to the JS import and preload in css.
Basically, the resulting HTML should be something like this:
<link rel="preload" href=".....all.css">
Notice the "async" word/attribute in the end of link tag above. It should be possible to use "defer" too.
On https://helpx.adobe.com/experience-manager/kb/optimize-aem-site-performance.html, I have found a library that can do this at Github https://github.com/nateyolles/aem-clientlib-async
But unfortunately this code is not compatible with the latest AEM 6.4.
Anyone has any idea, how to solve this issue??
Solved! Go to Solution.