Alert user that data is updated  in UI
                            
                         
                        
                     
                 
                
                    Suppose 2 users logged in from 2 different locations and seeing the same data
 For example 1 user updates the data and close him browser.
Whereas the second user is still in the same page with refreshing it.
How can we alert the user saying that the data you are seeing is already updated.