What’s new in Mail on Mac?
The Mail app in macOS Catalina offers new features for sending, receiving, and viewing email messages.
You can unsubscribe from mailing lists directly in Mail while reading your email.
You can mute conversations to reduce noise in your Inbox from overly active threads.
You can block messages from specific senders and move their messages directly to the Trash when they arrive.
You can view messages in a simplified column layout, with the message preview below or next to the message list.
You can highlight conversations in the message list so they’re easier to spot.
You can sign attachments using your nearby iPhone or iPad before you send them.
You can insert sketches from your nearby iPhone or iPad directly into a message you’re writing.
See alsoMail Support website