A number of people have embraced Live Preview, even though it is still under development. It is already an impressive piece of work.
LP hides the header hashes when the line is not active. Some people prefer to keep the hashes visible in order to see what level header they are dealing with when they encounter it.
@NothingIsLost has kindly provided code (“hacky code”, according to himself), which I have added to the Github repository. The link to the Github repository is given in the OP at the top of this page. On the Github page scroll down to Headers.md and click on it to open, and scrll all the way down.
Enjoy.