Scenario:
1. Change Editor to the "HTML" mode.
2. Paste the following text:
<span class="button primary">
<span style="color: red">
test
</span>
</span>
3. Change to the "Design" mode.
4. Change to the "HTML" mode.
Actual Result:
<span class="button primary" style="color: red;">
test
</span>
Two <span> tags merged into the one. Is it expected?