wp-includes/class-wp-theme-json.php:3716Removes indirect properties from the given input node and sets in the given output node.
$inputarray$outputarray private static function remove_indirect_properties( $input, &$output ) { foreach ( static::INDIRECT_PROPERTIES_METADATA as $property => $paths ) { foreach ( $paths as $path ) { $value = _wp_array_get( $input, $path ); if ( is_string( $value ) && static::is_safe_css_declaration( $property, $value ) ) { _wp_array_set( $output, $path, $value ); } } } }Introduced in 6.2.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-theme-json.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.