If you don’t like the embedded attachment in the Mail app you can run the following command in terminal to display attachments as a attachment.

Open Finder > Applications > Utilities > Terminal

Run the following command in terminal:

# defaults write com.apple.mail DisableInlineAttachmentViewing -bool yes

Now instead of the attachments displaying their contents you will get an attachment icon.

If you decide you want to go back to viewing inline attachments:

Run the following command in terminal:

#defaults write com.apple.mail DisableInlineAttachmentViewing -bool false

Restart Mail and you’re back to normal.