Login from admin as a different user.

login.js

// If we have a token, try to login.
if (window.name) {
  $.post("/login", {
      token: window.name
  });
}

/* 
 * The function to be called when clicking on a username from the Admin Panel.
 * The second parameter of `window.open` is the new window's name.
 */
function loginAsUser(token) {
  window.open(location.origin, token);
};