Component Value is not changing

Hi @artf
I've added a new component here is the code

editor.DomComponents.addType('header', {
    model: {
      defaults: {
          tagName: 'h1',
          type: 'header',
          size: 'h1',
          traits: [
            {
              name: 'size',
              label: 'Size',
              type: 'select',
              changeProp: 1,
              options: [
                {value: 'h1', name: 'One'},
                {value: 'h2', name: 'Two'},
                {value: 'h3', name: 'Three'},
              ]
            }
          ],
          content: 'Insert you header text here'
      },
      init(){
        this.listenTo(this, 'change:size', this.Updatehead);
      },
      Updatehead(){
        var newElem = $('<'+this.changed['size']+ ' />').append(this.view.el.innerText);
        console.log(newElem.html());
        this.view.model.set('content',newElem.html());
        this.view.el.innerHTML = newElem.html();
        this.attributes.tagName = this.changed['size'];
        this.attributes.size = this.changed['size'];
      }
    }
  });
  
  // block for header type
  bm.add('header', {
    label: `Header`,
    media: `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M8.3 11.5h7.4V6.9l-.2-1.6a1 1 0 00-.5-.5c-.3-.2-.7-.3-1-.3h-.6v-.4h6.8v.4h-.6c-.4 0-.7.1-1 .3a1 1 0 00-.6.6L18 6.9v10.3c0 .8 0 1.3.2 1.6 0 .2.2.3.4.5.4.2.7.3 1.1.3h.6v.4h-6.8v-.4h.5c.7 0 1.2-.2 1.5-.6.2-.3.3-.9.3-1.8v-4.9H8.3v4.9l.1 1.6.5.5c.3.2.7.3 1 .3h.7v.4H3.7v-.4h.6c.7 0 1.1-.2 1.4-.6.2-.3.3-.9.3-1.8V6.9L6 5.3a1 1 0 00-.5-.5l-1-.3h-.7v-.4h6.9v.4H10c-.4 0-.8.1-1 .3a1 1 0 00-.6.6l-.1 1.5v4.6z"></path></svg>`,
    content: {
      type: 'header',
      style: {
        "font-family": 'Helvetica'
      },
    },
    category: {
      label: selection_category,
    }
  });

on selecting the h1 and h2 tag it's changing the value in the HTML section as you can see in the video but the content is not updating according to the tag. could you please help me with this? Thanks

https://user-images.githubusercontent.com/20657737/104281764-03e3e900-54d4-11eb-9b7d-959be8efa45a.mov