References

script.js

function myFunction() {
  const sid = "YOUR_SID";
  const cookie = "connect.sid=" + sid;
  const userInfoJSON = UrlFetchApp.fetch("https://scrapbox.io/api/users/me", {
    method: "get",
    headers: {
       "Cookie" : cookie
    }
  });
  const userInfoData = JSON.parse(userInfoJSON);
  const csrfToken = userInfoData.csrfToken
  const response = UrlFetchApp.fetch("https://scrapbox.io/api/page-data/export/blu3mo.json", {
    method: 'post',
    headers: {
       "Cookie" : cookie,
       "X-CSRF-TOKEN": csrfToken,
    },
    muteHttpExceptions : true,
  });
  Logger.log(JSON.parse(response))
}