twicli for Rambox ( http://rambox.pro )

customCode.js

var originalTitle = document.title;
function updateTitle() {
  document.title = document.querySelectorAll('#reply.new, #direct.new').length > 0 ? '(\u2022) ' + originalTitle : originalTitle;
}
registerPlugin({
  newMessageElement: updateTitle,
  newDM: updateTitle,
  switchTo: updateTitle
});