class Capybara::Cuprite::Browser::Page

def go(delta)
  history = command("Page.getNavigationHistory")
  index, entries = history.values_at("currentIndex", "entries")
  if entry = entries[index + delta]
    @wait = 0.05 # Potential wait because of network event
    command("Page.navigateToHistoryEntry", entryId: entry["id"])
  end
end