1. Log into your Jira Cloud instance as a user with Jira administrator rank.
2. Click on on Jira Settings:.
3. Next, click on Apps, on the newly loaded left-hand side panel:
and go to Find new apps..
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4. Locate Issue Links Viewer via "search the marketplace" field - please note that its Vendor is Transition Technologies PSC:
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5. Click Click Try free to to begin a new trial or or Buy now to to purchase new license for for Issue Links Viewer
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6. Enter your necessary information and click click Generate license when when redirected to MyAtlassian
7. Click Click Apply license