Comment by KomoD

All of these domains are already widely known because Guerrilla Mail are the ones actually running the email service, his website is a wrapper with a CORS proxy.

He doesn't own or operate the cors proxies, mail infra, domains or the api

https://www.guerrillamail.com

And the entire app was just generated with https://aistudio.google.com

(check view-source: and you'll see "aistudiocdn.com" for all the imports)