wp-includes/sodium_compat/src/Core/Base64/Original.php:35Encode into Base64, no = padding
$srcstringstring public static function encodeUnpadded($src) { return self::doEncode($src, false); }Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/sodium_compat/src/Core/Base64/Original.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.