Pretty much like in Outlook, Thunderbird, Windows Live Mail, or Gmail on tables, you can now split vertically or horizontally the view of your emails when using Gmail on a web browser. On the left side of the screen you’ll see a list with all your emails and a small hint of the initial text of the main message content, and in the right side you’ll see the content of a particular email.

Once the feature is enabled and you return to the inbox, you will notice a new toggle button in the top-right-corner of your message list that will let you switch between preview and list views.

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