Facebook invite all code

The code below worked all the time when inviting my friends to my bands event. Now this code is not working and can't seem to find one that works with Safari. What's wrong? Is there a setting in preferences? Is there a new code? It's driving me nuts and tired of clicking 500 + people manually. Thanks for any help.

javascript:var x=document.getElementsByTagName("input");for(var i=0;i<x.length;i++) {if (x[i].type == 'checkbox') {x[i].click();}}; alert('Done: please scroll and repeat until all your friends have been selected');