# The Page Visibility API

The Page Visibility API 
is useful for removing listeners (or stopping background processes) from hidden tabs or pages. 

You only have to register a visibilitychange listener:     


document.addEventListener('visibilitychange', _ => { 
    const state = document.visibilityState;
    console.log('document is: ',state);
})    


Hiding the page / making it visible again prints:    


document is:  hidden
document is:  visible    


See it in action:    





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