Render headlines and non-headlines in blocks differently

Current behavior:

Given:
image

It is saved in the text file as the following:
image.

This is concerning because in other editors (i.e Emacs) it is fontified as the following:
image

It can be visually confusing when trying to organize blocks in a way also compatible as a text file.

Ask:
I feel we should render the header distinctly from the rest of the block’s body