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All custom modules', features', processes', dashboards', reports', printouts' and Web APIs' IDs should begin with the word CUSTOM. All custom feature menu option IDs should begin with the word CUSTOM as well.
Create Custom Feature
In the following example, two new features are added to Subscriptions module. To add a new feature to an existing module, you simply have to use the existing module's ID, overriding this way the system's release functionality.
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