title: redactor.js: Prevent backspace at beginning of div-container
body: <p>I'm using the redactor.js-editor, which works with editable div-container. If there are multiple wrapped contenteditable container, I got the problem, that if I delete content with the backspace-button I can delete the container, so that the complete code mess up.</p>
  
  <p>My question is: Can I prevent the backspace-function via javascript if the cursor is at the beginning of a div-container?</p>