Eliminiate flash[:notice] or flash[:errors] being shown on back button by forcing non-cache of page

app.rb

before do
    if flash[:notice] || flash[:errors]
      response.headers["Cache-Control"] = "no-cache, no-store, max-age=0, must-revalidate"
      response.headers["Pragma"] = "no-cache"
      response.headers["Expires"] = "Fri, 01 Jan 1990 00:00:00 GMT"
    end
end