Prevent copy-paste and contextmenu

PreventCopyPaste.js

document.oncontextmenu = function(event) 
{
  event.preventDefault();
  event.stopPropagation();
  return false; 
};

document.addEventListener('contextmenu', function(event)
{
  event.preventDefault();
  event.stopPropagation();
  return false;
});



document.onkeydown = function(event)
{
  event.preventDefault();
  event.stopPropagation();
  return false;
});

document.addEventListener("keydown", function(event)
{
  event.preventDefault();
  event.stopPropagation();
  return false;
});



https://developer.mozilla.org/en-US/docs/Web/API/Document/selectstart_event

// addEventListener version
document.addEventListener('selectstart', function(event) 
{
  event.preventDefault();
  event.stopPropagation();
  return false; 
});


// onselectstart version
document.onselectstart = function(event) 
{
  event.preventDefault();
  event.stopPropagation();
  return false; 
};


// https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Building_blocks/Events
// https://developer.mozilla.org/en-US/docs/Web/API/Event/returnValue
// https://stackoverflow.com/questions/5963669/whats-the-difference-between-event-stoppropagation-and-event-preventdefault
// stopPropagation stops the event from bubbling up the event chain.
// preventDefault prevents the default action the browser makes on that event.