"After leaving MDN, I took on a dual role: WADI (Web Advocacy & Developer Initiative) and Firefox OS for TV Partner Engineering. With WADI I had the pleasure of contributing to the Service Worker Cookbook. With the TV role I got a beautiful 60" ultra HD TV where I helped partners bring their video sites and games to life."
it seems there are some jobs at Mozilla that might not necessarily contribute significantly to its success.
And it looks like overall management in Mozilla is not in the greatest shape:
"When things got a bit tough at Mozilla, I shifted to Mozilla's "Productivity Tools" team. My first two weeks were nothing short of hilarious; my new manager didn't know I was a front-end engineer, so I stumbled through completing a big python migration."