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Log into your Jira instance as an Administrator.
Click Settings ⚙️ in the upper right corner.
Select Apps.
In the left-hand panel, click Jira Misc Custom Fields.
Select My custom fields.
Click New custom field in the upper right corner.
Give the custom field a name and, optionally, a description. Note: the maximum length of both the name and description fields is 255 characters.
Select the JMCF field type and click Next.
Follow the steps in the next section to configure your custom field.
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