wp-includes/ID3/module.tag.id3v2.php:3736$framenamestring$id3v2majorversionintbool|int public static function IsValidID3v2FrameName($framename, $id3v2majorversion) { switch ($id3v2majorversion) { case 2: return preg_match('#[A-Z][A-Z0-9]{2}#', $framename); case 3: case 4: return preg_match('#[A-Z][A-Z0-9]{3}#', $framename); } return false; }Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/ID3/module.tag.id3v2.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.