Editor doesn't break heading style on new line even if e

When editing for example content block, I select h3 style, write something, then press enter, having the cursor on new line I set style to normal, editor continues to insert text into h3 tag, resulting output:

<h3>title
<p>text<br />
<br />
</p>
</h3>

should be:

<h3>title</h3><br /> 
<p>text</p>

How is the user supposed to make text under heading normal text if she doesn't know HTML?

opened support ticket for this