Displaying and Composing Messages Options

Under the preferences option in settings there is also the Displaying Messages section and Composing Messages section. These sections give you useful options to choose between when composing and displaying messages. Probably the most important options would be the Open message in a new window and Compose message in a new window Settings.

Open message in a new window is located under Displaying Messages:

Compose message in a new window is the first option under Composing Messages: