Since all different email services like Gmail, O365 build and construct emails in a different way, therefore, currently how the email is processed in Jira is different. For example, when Outlook sends an email with multiple addresses in the To list to Jira service desk email channel (each address is for the support channel in a different project), it will send it as one message with multiple envelope recipient addresses (RCPT TO in the SMTP session). Whereas, Gmail, on the other hand, would send a separate email for each recipient.

Therefore, for the email sent by Outlook, only one ticket is created in the project which is listed first in the To list (rest are ignored), whereas, in Gmail's case, two separate tickets are created in the respective projects.

This feature request is to improve this behavior and bring uniformity to how Jira processes incoming emails.