Pros
Open source company, modern offices, free snacks, free travel, flexible work hours.
Cons
No product direction. Last 2 years of my life feel wasted. Terrible management that is tone-deaf to feedback. An internal survey showed that employees are disappointed by management. The CEO dismissed questions about it at an all-hands as "misunderstanding". Nepotism and politics everywhere. Uninspiring CEO pushed out all worthwhile executives and replaced them with his cronies, friends and failed former co-founders. Goals are set, missed and then buried. CEO spends most of his time on internal marketing to convince people things aren't as bad as they are instead of making things better. Few career opportunities for females and minorities. You have to be male and white to get promoted or be a director or executive at Mozilla.