curl --request GET \
  --url https://discord.com/api/v10/channels/{channel_id}/thread-members \
  --header 'Authorization: <api-key>'

[
  {
    "id": "<string>",
    "user_id": "<string>",
    "join_timestamp": "2023-11-07T05:31:56Z",
    "flags": 123,
    "member": {
      "avatar": "<string>",
      "banner": "<string>",
      "communication_disabled_until": "2023-11-07T05:31:56Z",
      "flags": 123,
      "joined_at": "2023-11-07T05:31:56Z",
      "nick": "<string>",
      "pending": true,
      "premium_since": "2023-11-07T05:31:56Z",
      "roles": [
        "<string>"
      ],
      "user": {
        "id": "<string>",
        "username": "<string>",
        "avatar": "<string>",
        "discriminator": "<string>",
        "public_flags": 123,
        "flags": 0,
        "global_name": "<string>",
        "primary_guild": "<unknown>",
        "bot": true,
        "system": true,
        "banner": "<string>",
        "accent_color": 123,
        "avatar_decoration_data": "<unknown>",
        "collectibles": "<unknown>"
      },
      "mute": true,
      "deaf": true,
      "avatar_decoration_data": "<unknown>",
      "collectibles": "<unknown>"
    }
  }
]