The old method mentioned in similar questions here is the following:
var editor = ace.edit("editor");
var Range = ace.require('ace/range').Range;
editor.setReadOnly(true);
editor.setTheme("ace/theme/github");
editor.getSession().setMode("ace/mode/javascript");
editor.getSession().addMarker(new Range(1, 0, 15, 0), "ace_active_line", "background");
Unfortunately it doesn't work, as you can see here:
http://jsbin.com/acotuv/1/edit
Any suggestions?