I think the reason Firefox has been making all these horrible decisions lately is quite clear if you think about it. Everybody on the Firefox team knows they're on a sinking ship, and therefore each person's top priority is to not be fired in the next round of layoffs. How do you avoid that? You do stuff so you have a record to point at and say "look at how much I've contributed to Firefox". Doesn't matter if your changes are idiotic so long as you personally seem important.