Gmail gains new machine learning models to block phishing and spam messages
The new security update includes early phishing detection using machine learning, click-time warning for malicious links, as well as unintended external reply warnings.
As mentioned earlier, Gmail is now displaying unintended external reply warnings to users, which is meant to help prevent data loss. For example, whenever you try to respond to someone outside of your company domain, Gmail will warn you to make sure that you intend to send that email.
Most of these new security features are meant to protect companies data and help employees avoid scams and phishing attempts. It's nice though that Google continues to add built-in defenses against new security threats more often than not.
source: Google
Things that are NOT allowed: