Arguments:
Node
, Element
, Dom
String
Checks the position of caret at the editable block.
let caret = this.app.create('caret');
let isEnd = caret.is(element, 'end');
Arguments:
Node
, Element
, Dom
String
Sets the caret at the specified position.
let caret = this.app.create('caret');
caret.set(element, 'start');