Markdown Previewer doesn't pass the tests

I created this pen: https://codepen.io/juggler39/pen/XWavyxz
It looks like everything works, but it doesn’t pass the tests 5 and 6.
I can clearly see in developer tools, that the markdown is present, but the test insists, that it is missed.
I don’t have any clue what to do.
Please help.

This has been solved here:

Thank you very much! It works.