While Editor is open and working on new message look in Message menu, way up top on toolbar, and Font or use keystrokes alt-m-f.
To set default for Reader while viewing message look in Reader menu, Font or use alt-r-f keystrokes.
The f at far left in the message toolbar is for making changes within a message when Editing a Rich Text message. Your set Editor font from the top toolbar setting is the current default and same also in the signature Editor too. Font changes you make during message creation are not what is sent out when creating a plain text message, which carries no font information like a Rich Text or HTML message does.
When reading plain text message your default Reader font is used. When reading Rich Text (HTML) message font and color and size are controlled by the sender and is coded into the message source.
<p>While Editor is open and working on new message look in Message menu, way up top on toolbar, and Font or use keystrokes alt-m-f.</p><p>To set default for Reader while viewing message look in Reader menu, Font or use alt-r-f keystrokes.</p><p>The f at far left in the message toolbar is for making changes within a message when Editing a Rich Text message. Your set Editor font from the top toolbar setting is the current default and same also in the signature Editor too. &nbsp;Font changes you make during message creation are not what is sent out when creating a plain text message, which carries no font information like a Rich Text or HTML message does.</p><p>When reading plain text message your default Reader font is used. When reading Rich Text (HTML) &nbsp;message font and color and size are controlled by the sender and is coded into the message source.&nbsp;</p>