Convert Google Analytics cookies to Local/Session Storage
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                David Murdoch
            
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        Published on 2010-12-21T17:29:24Z
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Google Analytics sets 4 cookies that will be sent with all requests to that domain (and ofset its subdomains). From what I can tell no server actually uses them directly; they're only sent with __utm.gif as a query param.
Now, obviously Google Analytics reads, writes and acts on their values and they will need to be available to the GA tracking script.
So, what I am wondering is if it is possible to:
- rewrite the __utm*cookies to local storage afterga.jshas written them
- delete them after ga.jshas run
- rewrite the cookies FROM local storage back to cookie form right before ga.jsreads them
- start over
Or, monkey patch ga.js to use local storage before it begins the cookie read/write part.
Obviously if we are going so far out of the way to remove the __utm* cookies we'll want to also use the Async variant of Analytics.
I'm guessing the down vote was because I didn't ask a question. DOH!
My questions are:
Can it be done as described above?
If so, why hasn't it been done?
I have a default HTML/CSS/JS boilerplate template that passes YSlow, PageSpeed, and Chrome's Audit with near perfect scores. I'm really looking for a way to squeeze those remaining cookie bytes from Google Analytics in browsers that support local storage.
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