How to load third-party javascript tag asynchronously which has [removed]

Question

We give out a piece of javascript tags such as which site owners put on their site like http://exa

Answer 1

Another procedure is to change the behavior of document.write() function.
Assume you have the main index.php file:

Hello

and the jsfile.js is like this:

document.write("OK MAN!");

now if you type doit() in the js browser console to execute that function (and the script do what you wrote) then the result would be:

Hello
OK MAN!

In which the html is like this:

Hello




OK MAN!