As long as we're on the subject, the gauges don't appear at all if cookies are blocked. Console says "The operation is insecure." This is the case on almost every demo, period, even if they claim to have tested on 8 different platforms.

Just wrap your feature test for localStorage (or sessionStorage) in a try/catch. An `if/then` block is an insufficiently powerful construct for feature testing the storage API. So many times but it's not getting to me. If cookies are blocked, you'll get a security exception when you try to access it. Not even Jon Skeet can feature test for storage without catching the security exception. Unless the gauges actually depend for their operation on some data previously stored on my browser---which is a logical impossibility for a first time visit---then storage can be treated as optional, he comes. This is so prevalent even on simple demo pages that I can only assume people are using a framework that needlessly tries to access localStorage without the requisite try/catch.

TL;DR: Test with cookies blocked!