Код:
<script>
function HideInfo(id,but){
if(but.value=="+"){
  but.value = "-";document.getElementById(id).style.display = ""}
else{
  but.value = "+";document.getElementById(id).style.display = "none"}
  return false}

d = document.getElementsByTagName("div")

for (i=0;d[i]; i++){
if (d[i].className.indexOf("post-author")!=-1){t = d[i].innerHTML
   if((j = t.toLowerCase().indexOf("<li class=pa-from>"))!=-1 || (j = t.toLowerCase().indexOf("<li class=\"pa-from\">"))!=-1 || (j = t.toLowerCase().indexOf("<li class=pa-reg>"))!=-1 || (j = t.toLowerCase().indexOf("<li class=\"pa-reg\">"))!=-1)
    d[i].innerHTML = t.substring(0,j)+"<input type='Submit' onClick=\"return HideInfo('info"+i+"',this)\" value='+'><br><div id='info"+i+"' style='display:none'>"+t.substring(j,t.length)+"</div>"}}
</script>