To enable any of GitHub’s API Previews, pass the previews option to the GitHub constructor
const octokit = new Octokit({previews: ["mercy-preview"],});
Previews can also be enabled for a single request by passing the mediaType.preview option
const {data: { topics },} = await octokit.repos.get({owner: "octokit",repo: "rest.js",mediaType: {previews: ["symmetra"],},});