_About Application Links
When you want to integrate two Atlassian applications, you set up an application link between them. Applications linked this way can share information and access each other's functions. For example, if you link Jira Software and Confluence, you can view Jira issues on a Confluence page using the Jira Issues macro. You can even link your individual projects, spaces and repositories across the different applications.
The Application Links plugin is bundled and shipped with the Atlassian applications. You cannot install it yourself.