How to accelerate JavaScript loading and execution

Javascript has a silent blocking feature, that is, when the Browser executes Javascript code, it cannot do anything at the same time,

Javascript has a silent blocking feature, that is, when a Browser executes Javascript code, it cannot do anything else at the same time, whether its code is embedded or external.

When a browser encounters a script tag that introduces an external JS file, it stops all work to download and parse and execute it. In this process, page rendering and user interaction are completely blocked, to avoid page loading pauses or even the appearance of blank pages, JS scripts should be placed at the bottom of the page as much as possible. This is very important:

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