Wallboard view of Custom Content is unavailable

Problem

If I switch my Jira dashboard containing a Custom Content gadget to wallboard view, the gadget doesn't show at all.

Solution

Currently, there is no solution for this available since Atlassian does not offer wallboard rendering for Forge apps.

You can still have a look at Atlassian's open ticket about the subject and vote for adding this feature or inform them about your use cases for the latter.