The "what happened" and "what expected" fields for user contributions can lose their newline formatting.
The contribution fields become single paragraphs, much harder to understand than they were in the form text areas before pressing "create!"

Some examples may include contributions 309, 436, 445, 455. 
I haven't seen examples in bug reports entered by LAMP, that submission code path may not be affected. I've also seen possible counter-examples in user contributions, e.g. 411, 412, 414

As a workaround, I and possibly others (contrib 451) have sometimes been putting non-trivial "what happened" and "what expected" descriptions in the code area instead.

(In case it is relevant, I'm using Firefox on Windows.)