GET

https://api.github.com/notifications/threads/thread_id/subscription

This checks to see if the current user is subscribed to a thread. You can also get a repository subscription.

Note that subscriptions are only generated if a user is participating in a conversation--for example, they've replied to the thread, were @mentioned, or manually subscribe to a thread.

Scopes requested: user, public_repo, repo, notifications, gist
Authorization
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