Comment by currysausage

Yeah, I fell into that rabbit hole once. Tried all abuse channels that I could find. network-abuse@ refers you to the Google Cloud abuse form. They ‘are not able to take action on this report since the IP mentioned in the report is not hosted on Google Cloud.’ Gmail abuse doesn’t even bother to reply (why should they, it’s not about Gmail after all). In the end, I just blocked DKIM identifiers related to Firebase via Rspamd.