Summary

Currently, the ViewIssueModal class https://developer.atlassian.com/platform/forge/apis-reference/jira-api-bridge/viewIssueModal/ doesn't have a listener to open a different issue key on demand; the issue key is fixed by the context.

The problem occurs when the viewed issue contains linked work items. When a user clicks on a linked work item (inside the modal):

• The content of the ViewIssueModal does not update to the newly selected issue.

• Instead, the clicked work item opens behind the modal, in the location where our Forge app was previously rendered.

Suggestion

Add an onChangeIssue or similar listener so that when the user clicks a linked work item, the modal changes to the clicked issue key instead of opening in the background. 

Workaround

Currently, there is no workaround to open a new issue key in the same modal and keep the app open.

The closest we have is to use router.open() instead of ViewIssueModal.
  
  Benefits:
  ✓ Linked issues work normally - users can click and navigate through links
  ✓ Native Jira experience - familiar to all Jira users
  ✓ No modal limitations - no navigation context issues
  Trade-off:
  x Closes your Forge app when viewing an issue
  x Users navigate away from your app UI