In a recent project, I had to send data between two subdomains on a site. Unfortunately, this meant I had to deal with browsers' same origin policy. The canonical solution to this is to set up Cross-origin resource sharing (CORS) , but this is a bit of a pain to do[^1] - especially if you're only making one or two cross-domain requests - and it isn't supported by some older browsers. Luckily there are some alternatives.
