I had a need to include a body with a message from a mailto. I found this reference useful.


Feature Syntax
Address message to multiple recipients , (comma separating e-mail addresses)
Add entry in the “Subject” field ?subject=Subject Field Text
Add entry in the “Copy To” or “CC” field ?&cc=id@internet.node
Add entry in the “Blind Copy To” or “BCC” field ?&bcc=id@internet.node
Add entry in the “Body” field ?&body=Your message here”>MailTo Syntax: “The MailTo command can do more than enter a single e-mail address in the ‘Send To’ field while activating your e-mail program. It can also:
Feature Syntax
Address message to multiple recipients , (comma separating e-mail addresses)
Add entry in the ‘Subject’ field ?subject=Subject Field Text
Add entry in the ‘Copy To’ or ‘CC’ field ?&cc=id@internet.node
Add entry in the ‘Blind Copy To’ or ‘BCC’ field ?&bcc=id@internet.node
Add entry in the ‘Body’ field ?&body=Your message here”