Pretty much that. I just did a longish post with a bunch of markdown, shuttling back and forth between Preview and Edit. In Edit, there seemed to be extra line breaks but it looked okay in preview. Then I posted, made another edit, and all the line breaks disappeared so now a long post with a lot of formatting and images is a wall of text.
Here’s a link to the original document, in Google docs (think the permissions are okay). I downloaded it as an md then dropped it into the micro.blog web posting form. I knew it would need some tweaking, like uploading images then pasting the md code from within micro.blog.
It looked like there were double paragraphs initially, so I deleted the duplicates, and it looked fine in preview. Judging by some of the formatting changes as I did this, I think they might’ve been using linebreaks/newlines instead of paragraphs? I’m not sure whether md was playing well with html versions.