Add persistent flag of origin

web/src/entry.client.tsx

@@ -1,3 +1,4 @@
+import { hasFlag } from 'country-flag-icons'
 import { hydrateRoot, createRoot } from 'react-dom/client'
 
 import App from 'src/App'
@@ -15,6 +16,11 @@ if (!redwoodAppElement)
       "exists in your 'web/src/index.html' file."
   )
 
+if (!hasFlag(process.env.COUNTRY))
+  throw new Error(
+    'Invalid COUNTRY environment variable, please select a valid ISO-3166-1 alpha-2 country code\n See https://en.wikipedia.org/wiki/ISO_3166-1#Codes'
+  )
+
 if (redwoodAppElement.children?.length > 0)
   hydrateRoot(redwoodAppElement, <App />)
 else {