Created attachment 539093 [details] [diff] [review] Patch to fix The HTML5 parser doesn't output isindex elements for <isindex> markup any more. Instead it outputs a couple of <hr>s and an <input>. So layout no longer needs to have support for isindex frames.
Comment on attachment 539093 [details] [diff] [review] Patch to fix r=dbaron Once you've removed the content code too, you should do an mxr search to make sure you haven't missed anything.
Landed on inbound http://hg.mozilla.org/integration/mozilla-inbound/rev/47d8748daa90