JS. How to call a callback before loading all components AS.js

You can redefine the actions of some components by writing your own version and adding these edits through the preInit callback. It will be called after loading the client part of the library, but before initializing these components (calling init methods in these components). 

as.callbacks = [];
as.callbacks["preInit"] = function(){
    	console.log("preInitCallback")
}

You can place this script in global JS (in Quick actions at the top right in the interface)

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