gitlab-org--gitlab-foss/app/assets/javascripts/sidebar/queries/epic_subscribed.query.graphql

query epicSubscribed($fullPath: ID!, $iid: ID) {
  workspace: group(fullPath: $fullPath) {
    __typename
    emailsDisabled
    issuable: epic(iid: $iid) {
      __typename
      id
      subscribed
    }
  }
}