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You can restrict email addresses or domains for the selected user functionality. While creating a link only the listed addresses/domains will be allowed to be used. Details on Project Configuration can be found in our documentation: https://docs.warsawdynamics.com/content/51354/external_share_for_jira_documentation/116195750/116195356 Project Configuration documentation.
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Email Subject & Body Customization
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For more details about Email template, please check our documentation: https://docs.warsawdynamics.com/content/51354/external_share_documentation/116196241/
However, you can also edit the email subject and email body of individual emails directly.
As you create External Share on Jira issue, board, filter or timeline, you will have access on screen to edit email contents once you click “Send via email.”
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