How to use POST while keeping CSRF as true

Some troubleshooting tips:

1. Make sure that you are actually executing the revised JavaScript by clearing the browser cache.
   
2. Use your browser's Developer Tool to examine the request header of the post. You should be able to see the CSRF values being posted
   
3. If you use $config['csrf_regenerate'] = TRUE; try setting it to FALSE until you figure out if that is the reason for the 403..
   

If you are using $config['csrf_regenerate'] = TRUE; then you will have to change what you return and how it is used in the success function. Let us know if you need help with that.