My EE.SE profile (where I have last edited it) looks like this:
But everywhere else my profile got copied (using SO as example) as
Is this by design or a bug?
Ha, nice find! The markdown was getting trimmed after the HTML was generated, and before it was sent over to other sites to update (which used the trimmed markdown to generate their HTML). So if you look at the about me markdown on EE.SE, it looks like:
A fix is rolling out in the next build (build rev
2015.11.11.3857 on MSE/MSO,
2015.11.11.2970 on sites). It fixes both issues (HTML being generated before markdown processing, as well as the markdown processing). Updating your profile after that should correctly update it everywhere.