How to set the caret (cursor) position in a contenteditable element (div)?

I have this simple HTML as an example:

<div id="editable" contenteditable="true">
  text text text<br>
  text text text<br>
  text text text<br>
</div>
<button id="button">focus</button>

I want simple thing - when I click the button, I want to place caret(cursor) into specific place in the editable div. From searching over the web, I have this JS attached to button click, but it doesn't work (FF, Chrome):

const range = document.createRange();
const myDiv = document.getElementById("editable");
range.setStart(myDiv, 5);
range.setEnd(myDiv, 5);

Is it possible to set manually caret position like this?

In most browsers, you need the Range and Selection objects. You specify each of the selection boundaries as a node and an offset within that node. For example, to set the caret to the fifth character of the second line of text, you'd do the following:

function setCaret() {
    var el = document.getElementById("editable")
    var range = document.createRange()
    var sel = window.getSelection()
    
    range.setStart(el.childNodes[2], 5)
    range.collapse(true)
    
    sel.removeAllRanges()
    sel.addRange(range)
}

<div id="editable" contenteditable="true">
  text text text<br>text text text<br>text text text<br>
</div>

<button id="button" onclick="setCaret()">focus</button>

IE < 9 works completely differently. If you need to support these browsers, you'll need different code.

jsFiddle example: http://jsfiddle.net/timdown/vXnCM/