But when you click 'Edit", the leading newlines are stripped from the post editor, making it look like the were never inserted in the first place.
This sounds like a feature to clear up useless newlines, not a bug.
I agree, and I think it should be better implemented...
I find line breaks at the beginning and end of posts useless. I've seen users abusing this "feature" to reserve more space in posts, or inserting double lines between paragraphs unnecessarily. This just makes me spend even more time scrolling with my mouse

I think this "bug" should be improved to eliminate all white space at the beginning and end of posts, as well as double spaces in the middle of paragraphs.