1. Deleting unnecessary "twitter:" meta elements to reduce code duplication, which "og:" meta elements can be used as fallback.
2. Re-arranging head elements in order to make parsing faster (theorically).
3. Changing self-closing elements typing from "/>" to ">".
4. Changing uppercase doctype declaration to lowercase ("DOCTYPE" to "doctype"), in favor of saving 4bytes when compressing via gzip or brotli.

Resources

Twitter and OG meta elements:

1. https://developer.x.com/en/docs/twitter-for-websites/cards/guides/getting-started
2. https://developer.x.com/en/docs/twitter-for-websites/cards/overview/markup

HEAD arrangment

https://github.com/rviscomi/capo.js

There is a problem that I didn't fix (couldn't) which is there is a<style> tag renders before<meta charset="utf-8"> which may be bad, because it's suggested to do that:

Every page must declare a character encoding of UTF-8, using either the charset meta tag or the Content-Type HTTP response header. When the meta tag is used, it must be discoverable within the first 1024 bytes of the document.