selectionStart and selectionEnd in contenteditable element

Question

I have been struggling the selectionStart and selectionEnd attributes of textarea to make them work with contenteditable d

Answer 1

This answer uses Selection#modify, which is non-standard, but at least, I suggest you to use "insertText" command:

function replaceVal(val, step) {
  var selection = window.getSelection();
  for (var i = 0; i < step; i += 1) {
    selection.modify('extend', 'backward', 'character');
  }
  document.execCommand('insertText', false, val);
}

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