Even if you're not watching a specific repository, you can subscribe to individual conversations that interest you.

  1. On GitHub Enterprise, navigate to the main page of the repository.

  2. In the repository's right sidebar, click Issues or Pull requests. Issues or Pull Requests tab selection

  3. In the sidebar on the right, click Subscribe. Conversation Subscribe button

Once you subscribe to a conversation, you receive every notification thereafter, as though you were participating in the thread.

Further reading