Hey there 
Just adding a quick update here, as this thread is quite old and a lot has changed since then.
The good news is that in Funnelish, you don’t need custom code for this anymore 
We’ve introduced much more flexibility in the editor, especially around phone inputs and country-related fields. Everything can now be handled directly within Funnelish — no need to load external country code lists or rely on custom scripts.
We’ve also created an updated guide that shows exactly how to set this up:
Country Code for Phone Numbers (New Funnelish Update)
If you need a hand with this (or anything else), just let us know — happy to help!