Unfortunately, despite multiple requests in the past and a heartfelt plea, Atlassian is still not very susceptive to external contributions.
The best thing you can do is try and find the developers that created the app, although there is a high change that they either moved on to built greater things within Atlassian or have left the company.
Alternatively, as with a lot of things Atlassian concerned, you can also join the ever growing choir of people screaming into the void.