There were no such comments on HN, thankfully. I didn't follow the story on reddit or twitter much myself, but I _did_ talk to a fair number of people at Mozilla during the goings on. (I work at Mozilla, if that wasn't clear.)

There were certainly mails or blog comments (I'm not sure which, and the two are equivalent anyway when comments are moderated) with such threats in response to Lars Lohn's blog post (quoted near the bottom of <http://www.twobraids.com/2014/04/back-into-light.html>).

Of course I have no way to prove that to you. An earlier version of Lars' post (before he deleted it in his fit of pique) had an explicit edit mentioning the threats, but even Google's cache now only has <http://webcache.googleusercontent.com/search?q=cache:eKzKHuO....

I'm told (more second-hand than in Lars' case, but by people I trust) that others received similar threats as well. Again, I have no way to convince you that this is true.