`str_starts_with()` and `str_ends_with()` were introduced in PHP 8.0 to perform a case-sensitive check indicating if the string to search in (haystack) begins or ends with the given substring (needle).
WordPress core includes a polyfill for these functions on PHP < 8.0 as of WordPress 5.9.
Follow-up to [55990], [56014].
See #58220.
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