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Log in as a user with the JIRA Administrators global permission.
Click the admin drop-down and choose Atlassian Marketplace and the Manage add-ons screen loads.
Use Keyboard Shortcut instead: g then g and start typing manage... .
Find ImpEx in a list of your installed add-ons and click the Update button that is displayed if an update is available.
You can select Action required option on the Manage add-ons page to get a list of all available updates on at your instance.