TinyMCE Editor removing and and putting   instead

Steps for problem reproduction:

1. Open WordPress Admin Dashboard (I use version 3.7);
2. Click on Page > Add Page;
3. On the editor, choose the “HTML” Tab;
4. Write <p>Lorem ipsum dolor sit amet</p><br> on the content area;
5. Choose the “Visual” Tab;
6. Choose “HTML” Tab back;

7. The code <p>Lorem ipsum dolor sit amet</p><br> lost its formatting and appears as:

   Lorem ipsum dolor sit amet
   
    
   

How to deactivate this TinyMCE issue to maintain the entirely original formatting? (I’m looking for a solution on JavaScript client-side of the editor)

Once you save it, the

tags are automatically added to the contents. It only removes it when you have a plain <p>....</p> but if you have <p class="something">...</p> it would preserve it.