localStorage is not sent to the server when you request a document. So now you threw out the ability to do server-side rendering. This is only fine if you've go

localStorage is not sent to the server when you request a document. So now you threw out the ability to do server-side rendering. This is only fine if you've got a application that always requires authentication, otherwise you risk server vs client mismatch, needless roundtrips, and DOM rewrites.