I received a similar suggestion using Google PageSpeed Insights:
Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.
Leverage browser caching for the following cacheable resources:
http://www.google-analytics.com/analytics.js (2 hours)
Thanks,
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Ah, I found the answer on a StackOverflow post:
PageSpeed Insights 99/100 because of Google Analytics – How can I cache GA?
TL;DR – Don’t worry about it, as any solution is likely to cause more problems than it’s worth.
If you’re curious, the replies offer lots of technical details, most of which are over my head, but for the technically advanced it might be interesting.
This is my favorite response to the OP’s question:
“…run the Google insights URL on Google insights itself, have a laugh, relax and get on with your work.” [link to full response]
Here’s an image of the results when you run PageSpeed Insights on itself:
http://i.imgur.com/4ThHDLX.png
;^]
