First Data Interaction

First, add a message "increasing" to the browser in contributions.messages. Next, add a "hello-world:increasing" message to the default panel to handle/respond to.

The meaning of the panel field can be found in the Creating A Custom Panel documentation.

Adding increasing button and broadcast handling to the panel

Next, add an increasing button to the interface, as well as an area to display num and receive broadcast messages for num changes.

Refresh extensions

Lastly, the new Open Hello World option will appear in the Panel -> Custom on the top menu bar, click it to open it.