If you want to have your paragraphs inside a block (only one carriage return, non-strict Markdown paragraphs) be visually spaced in preview mode, here is a solution straight from the devs themselves (thanks!) Add this to your CSS to get some visual line spacing between paragraphs, makes writing long text much easier if you dislike strict Mardown breaks:
.markdown-preview-view br {
content: '';
display: block;
margin-top: 10px;
}
Add this as well if you want to mirror that behavior in edit mode:
.CodeMirror pre.CodeMirror-line {
padding-bottom: 10px;
}