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If you want to install the add-on from Jira admin page, please follow the instructions below. (You have to be a JIRA Administrator in order to install Boomerang)
First, click on "Jira Settings" and then choose "Apps".
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2. Go there to "1. First, click Apps menu and go to Find new add-ons" page.
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3. Type "Boomerang" by SaaSJet in the search box and then click on it.
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