1. Click 'Select Guests to Invite'
2. Paste the following code into the address bar of your browser:
javascript:elms=document.getElementsByName("checkableitems[]");for (i=0;i<elms.length;i++){if (elms[i].type="checkbox" )elms[i].click()};
4. Hit 'Enter' - all friends should be selected now.
3. Click 'Submit'
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