Comment 2 for bug 1416570

Debugging further, I can change docs.js to stop an off by one error:

// Needed for code and pre
$(function() {
    var pre = document.getElementsByTagName('pre'),
        pl = pre.length;
    for (var i = 0; i < pl; i++) {
        pre[i].innerHTML = '<span class="line-number"></span>' + pre[i].innerHTML + '<span class="cl"></span>';
        var num = pre[i].innerHTML.split(/\n/).length;
        for (var j = 0; j < (num-1); j++) {
            var line_num = pre[i].getElementsByTagName('span')[0];
            line_num.innerHTML += '<span aria-hidden="true">' + (j + 1) + '</span>';
        }
    }
});

However I think we need to get :lineos: working with Sphinx as a more durable fix for this:
http://sphinx-doc.org/markup/code.html#line-numbers