The following scenarios (at the least) must be tested and validated before publishing v2.0:

• Using profile_name parameter for auto-completion of SMTP settings
• Send recipients, copy_recipients and blind_copy_recipients with varying roles.
• Check what happens when a NULL is sent for from_address (with + without SMTP profile).
• Test multi-line text in free-text properties: subject, body, location, prod_id, event_identifier.
• Test custom VCALENDAR instance using ics_contents parameter.
• Try to send malicious code using the ics_contents parameter.