SO jQuery Fiddle

Test Fiddle mainly for SO Questions jQuery 1.4.3, UI 1.8.5

by Nick Craver

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.5/themes/ui-lightness/jquery-ui.css">
<div id="edit" contentEditable="true"></div>
<button>Test</button>

CSS

#edit { 
    border: solid 1px #ddd;
    width: 300px;
    height: 200px;
    white-space: pre;
}

JavaScript

$("button").click(function() {
    alert($("#edit").getPreText());
});

$.fn.getPreText = function () {
    var ce = $("<pre />").html(this.html());
    if ($.browser.webkit)
      ce.find("div").replaceWith(function() { return "\n" + this.innerHTML; });
    if ($.browser.msie)
      ce.find("p").replaceWith(function() { return this.innerHTML + "<br>"; });
    if ($.browser.mozilla || $.browser.opera || $.browser.msie)
      ce.find("br").replaceWith("\n");

    return ce.text();
};