Many messages and newsletters encompass both rich and plain text versions, however. In Mac OS X Mail, if you prefer plain text, you have to invoke a menu command to see the clean and simple text-only version; or do you?
A hidden preference's tweaking can, thankfully, turn the pages in Mail: it will display plain text versions by default and move rich-text behind a menu command.
Make Mac OS X Mail Prefer Plain Text for Displaying Mail
To have Mac OS X Mail display emails' plain text versions by default:
- Make sure Mac OS X Mail is not running.
- Launch Terminal.
- Type "defaults write com.apple.mail PreferPlainText -bool TRUE'" (not including the quotation marks).
- Press Enter.
Note that rich-text only emails will still display in rich text automatically. To access the rich version for emails that contain both, you can select View | Message | Best Alternative from the menu.

