Show All Facebook Chat Messages

// Adds a button along with the other top buttons
// Fetches chat for the active chat

document.getElementById("u_0_16").innerHTML+='<br><button id="btnViewAllMessages" style="float: right" value="1" class="_42ft _4jy0 _3mv _517h" type="submit" ></i>Show All Messages</button>',document.getElementById("btnViewAllMessages").onclick=function(){document.getElementById("btnViewAllMessages").innerHTML="Loading messages...";var e=setInterval(function(){document.getElementById("btnViewAllMessages").innerHTML="Loading messages... ("+document.getElementsByClassName("_7hy")[0].innerHTML.substring(document.getElementsByClassName("_7hy")[0].innerHTML.indexOf("<span>")+6,document.getElementsByClassName("_7hy")[0].innerHTML.indexOf("</span>"))+")","Load Older Messages (<span>0</span>)"!=document.getElementsByClassName("_7hy")[0].innerHTML?document.getElementsByClassName("_7hy")[0].click():(document.getElementById("btnViewAllMessages").innerHTML="Message loading complete",clearInterval(e))},5e3)};