In Gmail, warning banners are displayed when responding to emails sent from outside of your organisation.
Now, Android warning banners are also displayed as you add new external recipients.
The message displayed will be, This invite is suspicious.
This conversation contains links to known phishing sites that may attempt to steal your information.
It will offer two options to the user to respond, Block or Accept anyway.
It has also been rolled out to other Google Suite applications like Google Docs, Sheets, and Slides.
source: www.techworm.net