Special Watchers
Bug watcher supports special watcher types additionally to users: external email addresses, project roles and groups.

External Watchers

Manage non-Jira users as project or filter watchers. Notification of external users is a long-awaited feature request by the Jira community. Bug Watcher allows users with Manage Watchers permission to add external email addresses to project watchers.
These external users will receive notifications for events where watchers are set in the Notification Scheme of the project.
Additionally to projects, Bug Watcher allows you to add external watchers to your filters.
Example Use Case
Your company has many customers to collaborate with. You set up a Jira project for your customers. You want to make sure that contacts of your customer receive notifications on key events made to their issues.
Instead of manually notifying the external users, you add them as project watchers.
As a result, your external users will receive emails on key events.
Example Use Case 2
Your company has many customers to collaborate with via a single Help Desk project in Jira. You store the name of the customer in a custom field of the tickets in your help desk project.
You want to make sure that contacts of all your customers will be notified of key events of the issues belonging to them.
Instead of manually notifying the external users, you create filters for each customer and you add the contacts as watchers of the corresponding filter.
As a result, your external users will receive emails on key events on the issues that belong to their company.

How to do it?

Project Roles and Groups as Project Watchers

Project roles and groups can also be set as watchers in the projects or issues.
Go to your Project. Choose Bug Watcher icon in the left sidebar and click on Watches.
Add users, email addresses, Project Roles and Groups to project watchers in the Manage Project Watchers section

Issue Watchers Custom field

Add the Issue Watchers custom field and add it to an Issue screen in your Project. You can add special watchers to the issue via the Issue Watchers custom field: users, email addresses, roles and groups.
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