Press CTRL+SHIFT+R to reload with an empty cache = first impression.
View source to see how scripts are provided.
Time is calculated when window.onload
fires.
Try with different browsers. The time difference varies a lot.
A.getJS was developed to be small enough (854 bytes, for reference LABjs is 4701 bytes) to include inline in HTML (no library required). While it downloads in parallel and preserves execution order, similar to Head JS it blocks render if inline scripts are included after the scripts in Firefox. A.getJS is used in production on AOL Autos. Like head.js and LABjs, if the chain is broken, race conditions may occur in browsers like IE and Safari that do not support async execution scripts.