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In our Related Emails issue panel you are able to view 
or reply 
to existing and send new emails.
View email
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Click on the email or the eye icon to view a email. You can also download any attachments on the opened email.
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Reply to email
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Click on the reply button to reply to the mail.
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Send new email
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When sending an email, users can add recipients as needed. The subject line is automatically set to the issue key followed by the issue summary. By default, the message body includes the text "Related to" followed by the issue key. This helps ensure that the email is properly associated with the relevant issue.