Using the new Mail drop feature in Yosemite, you can send an attachment of up to 5GB. Once you want to send an attachment larger than 20MB then the attachment is automatically uploaded to iCloud. With the following terminal command it’s possible to adjust downward the minimum file size of 20MB. As an example we use 10MB, launch Terminal and enter the command.
OS X Mail: Set minimum font size for HTML
When receiving e-mails containing HTML code in OS X Mail, you will notice that some e-mail messages comes with very small text. With this default write command it’s possible to set the minimum font size for text in HTML e-mails. In some cases changing the size of text will break the layout.
Disable the preview from attachments in mail
When you open an email with an attachment there will be automatically displayed preview. Through the Preferences menu of the Mail application there is no option to turn this feature off. You can disable the preview with the following command:
Disable the send-mail tone in OS X Mail application
When sending an e-mail in the standard OS X Mail application a swoosh tone will be played. This tone cannot be disabled through the standard mail settings. With the following defaults write command you can disable the sound.
OS X Mail: Display e-mails in plain text format
If you have problems with HTML emails received in OS X Mail, you can force the Mail app to display e-mails in plain text using the following defaults write command.
Copy & Paste only the Email address in OS X Mail
When copying an email address from OS X Mail application and paste it somewhere in Mac OS X, you get the contacts fullname as well as their email address (“Tim Cook
Disable reply animation in OS X Mail
If you use Mail you have probably seen the animation when replying to a message. The message seems to slide off the screen. It’s possible to disable this animation: