In an attempt to improve the user experience modern websites are using javascript more and more. If you are even remotely serious about performance then you need to
merge your script files and minify the result. Minification is the process of removing unnecessary characters from a resource to reduce the size of the file.
You need to verify your javascript because javascript tries to tolerate errors. I'm going to go out on a limb and say that this is stupid. It can lead to a situation where invalid javascript works in its full form, but fails when minified.
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