selectable.go
func (s *selectable) FindByXPath(selector string) *Selection {
	return newSelection(s.session, s.selectors.Append(target.XPath, selector).Single())
}
func (s *selectable) FindByXPath(selector string) *Selection {
	return newSelection(s.session, s.selectors.Append(target.XPath, selector).Single())
}
// FindByXPath finds exactly one element by XPath selector.