Problem:

The request to GET /rest/api/2/issue/issueIdOrKey returns a full representation of the issue for the given issue key, including a list of the linked issues (issuelinks).

However, If the linked issue belongs to another Jira instance (remote link), the REST end point's response body does not contain details about this link, returning only the issuelinks related to the own Jira instance.

Impact of this behavior:

1. It is not trusted information, as the information returned is incomplete;
2. There is no mention that there are remote links on this issue;
3. As there is no mention that the issue could have remote links, we need to issue 2 requests for each issue: one to the API  GET /rest/api/2/issue/issueIdOrKey, the other to /rest/api/2/issue/IssueIdorKey/remotelink, only to get the remote links (if any).
4. This means that we need to make 2 calls instead of 1 to find the issuelinks and doubling the number of calls on our instances (which are very huge) is not efficient.

 
Steps to reproduce

• At the Application Links, add a connection to another Jira instance;
• Edit an issue
• Add a link to another issue (same Jira instance)
• Add a second link to an issue located on the other Jira instance
• Call the REST API GET /rest/api/2/issue/issueIdOrKey

What is expected
JSON returned with the full representation of the issue, including the remotelink information (RELATIONSHIP, URL, TITLE).
 
What is observed instead?

• Only the first link is returned, with no indication that this issue does contains also a remote link.