At the end of last year Google launched the new Google Sites to the public. In Google Sites Classic it is possible to insert scripts. I've already checked the help center and the official Google blogs in English and Spanish and I can't find how to do the same.
Sources consulted:
- Google Sites Help Center
- A totally rebuilt Sites, customer-tested and open for business (Article on the launch of the new Google Sites for G Suite users and administrators)
- This is Google - Official Google Blog in Spanish
Although the new Google Sites has already graduated from the "Early Adopter Program (EAP)", which is a program through which Google invites some G Suite users to try new products and services, the functions that it currently includes are the which we could call minimal. This is based on the following statement taken from A totally rebuilt Sites, customer-tested and open for business
Translation: Customers can continue to use Classic Sites as we continue to add capabilities and improve new Sites.
More information: