Basic(browser) uploader always returns error

// /main/frontend/fields/general/class-upload-file.php
// Vaildate function does not returns anything when using basic(browser) uploader, and it always returns error
        function validate_file_value( $valid, $value, $field, $input ) {
            // bail early if empty
            if ( empty( $value ) ) {
                return $valid;
            }

            // bail early if is numeric
            if ( is_numeric( $value ) ) {
                return $valid;
            }

            if ( isset( $value['file'] ) ) {
                if ( ! $value['file']
                    && ! $value['id']
                    && $field['required']
                ) {
                    return sprintf( __( '%s value is required.', 'acf-frontend-form-element' ), $field['label'] );
                } else {
                    return $valid;
                }
            }
            return $valid;// Modification
        }

Vaildate function does not returns anything when using basic(browser) uploader, and it always returns error

We need to return $valid on end of function.