I'm trying to debug an Angular 6 application and run locally using ng serve --proxy-config proxy.conf.json.
My proxy.conf.json file is as follows: (target is obfuscated for security reasons)
{
  "/**": {
    "target": "http://my-main-application.com",
    "secure": false,
    "logLevel": "debug",
    "changeOrigin": true
  }
}
This works for most GET requests but fails for POSTs (see screenshot below). 

Is there something additional I need to do to allow the POSTs to get through successfully?
 
    