>>/10546/
Slight correction and improvement:

.innerOP {
display: inline-block !important;
max-width: 20% !important;
vertical-align: text-top !important;
}
.textBrowserBreaks {
display: none !important;
}
.divPosts {
display: inline-block !important;
max-width: 78% !important;
}
.postCell {
display: inline-block !important;
max-width: 20% !important;
vertical-align: text-top !important;
}
.opCell{
  max-height: 300px !important;
  overflow-y: auto !important;
}


The rest is left as an exercise for the reader.