title: Remove onmouseover event from DOM elements efficiently
body: <p>I have an HTML page that contains many onmouseover events. These events are linked to a,img,td and div tags.</p>
  
  <p>What is the most efficient Javascript way to remove all the onmouseover events, presuming the page has loaded.</p>
  
  <p>I'm not using jQuery.</p>
  
  <p>(the task is to remove unneeded tooltips when the page is accessed using touch devices)</p>