How to use tabs in Mail on OS X El Capitan
Mail is one of the apps that has gained great popularity in the latest versions of OS X, so if you've already tried it a bit, you'll know that it's now easier to play with different emails open at the same time on a single screen.
However, there is a small problem when using email on OS X , and this is noticeable when using full-screen mode for Mail where you have access to the multi-tab functionality.
How to access and use email tabs in the Mail app for OS X
- You need to open the 'Mail' app and then send the app in full screen mode by clicking the maximize button in the app's title bar.

- Write a new email by pressing Command + FEMALE At the same time, and if you don't want to complicate things too much, go to the email menu and select “New Message".

- Whenever you want a new email to appear as a tab, You just need to repeat the previous process. creating new additional compositions.

The best part is that you can find each new email at the top of the screen, no matter if you're in a Safari tab, a folder, or somewhere else.
Additionally, if you're in tabbed email mode , you can click on any tab to open or close an email.

Tabbed Mail Mode
A little mess with the eyelashes
If you exit the Mail app in full-screen mode, and if all the tabs you had open for writing an email are not instantly lost, a separate message composition window will open for each tab you had open.

This means that a number of tabs open for writing, reading, deleting, or opening an email will be on the screen, causing complete clutter.
