Configuring how external user interfaces open in Workplace
If you have a task in your process that calls an external service that has an
external implementation, you can configure how the external UI opens in Workplace.
You can use the embedInWorkplace=true|false custom property to specify whether the external UI opens in a new window or tab or is embedded in the Workplace page. By default, the external UI opens in a new window. If you opt for an embedded page, ensure that the external UI can be embedded in an iFrame.
For more information, see Invoking an external implementation by using a user task.