Pop up blocker API- how to check if user has it enabled

Question

I need to know when the user clicks on the button that triggers window.open if there is stable API/way to know beforehand if the user actively has

Answer 1

window.open() will mostly only be blocked if it was not triggered by a click event.

To confirm the window has loaded:

var loaded = false;

function windowLoaded() { 
  alert("The popup loaded"); 
  loaded = true
}

function pause(milliseconds) {
  var dt = new Date();
  while ((new Date()) - dt <= milliseconds) { /* Do nothing */ }
}

document.write("start...");

//open the window
var win = window.open("window.html");

// If window.open returned an object
if(win) {
  win.onload = function() { 
    win.RunCallbackFunction = windowLoaded; 
  };
  document.write("popup sent...");

  pause(3000);

  // Verify that out window loaded
  if (loaded == false)
    document.write("check you popup blocker!");
  else
    document.write("ok!");

}
else {
  document.write("window.open() was blocked...");
}