not sure if required, changeOrigin allows your host target to be different from current environment

Author: Dan Kelley

src/client/src/setupProxy.js

@@ -1,9 +1,9 @@
 const proxy = require('http-proxy-middleware');
 
-
 module.exports = function(app) {
     app.use(proxy('/api/**', {
-            target: process.env.IS_LOCAL === 'true' ? 'http://localhost:3333' : 'http://server:5000'
+            target: process.env.IS_LOCAL === 'true' ? 'http://localhost:3333' : 'http://server:5000',
+            changeOrigin: true,
         }
     ));
 }