Custom JSON Body for JIRA Webhooks

Problem Definition:

Currently, we have a pre-configured event to be choose for webhook triggers. When it is triggered, it will send the same information about the changes to the target URL. While there are many options to choose, it is still not possible to set a Custom JSON body to the target URL.

Suggested Solution:

If there is an option to configure a custom JSON body which will be sent out when the webhook is triggered, it will be great. Some external application could use this and there is a possibility that it does not accept the format that JIRA send out.