I'm using code mirror for the first time and finding it to be awesome!

So, when the page loads for the first time, the cursor goes before line number. But after I type couple of lines, all the texts start showing in proper area after line number. Any thoughts? These are the values that I've set.

var myCodeMirror = CodeMirror.fromTextArea(elt, {
  lineNumbers: true,
  mode: "xml",
  htmlMode: true, 
  lineSeparator: null,
  theme: "default",
  indentUnit: 2,
  tabSize: 4,
  indentWithTabs: true,
  lineWrapping: true, 
  tabindex: 1,
  autofocus: true,
  gutter: true,
  lineWrapping: true  
});
myCodeMirror.setSize(null,1000);