Due to Access-Control-Expose-Headers is not defined, cannot access these headers of ratelimit-limit, ratelimit-remaining, ratelimit-reset in browser javascript like single page app, beside https://dev.twitch.tv/docs/api/guide#rate-limits link explain.
I read https://discuss.dev.twitch.com/t/still-cannot-read-ratelimit-headers-from-javascript-in-the-browser/15761 and https://discuss.dev.twitch.com/t/getting-rate-limit-response-headers-in-javascript/12523/4