Any new Share action, by default, is not enabled, because not all actions are supported with Smart Folders (for example, data can’t be persisted with a Smart Folder).
Ensure that you conduct adequate testing before enabling an action for Smart Folders.
To enable the new action, add an evaluator in the appropriate action group definition in your module, or add it to the Tomcat shared/classes/alfresco/web-extension/smartfolders-amp-actions-config.xml file.