I'm just going to put this out there, I have absolutely no basis in fact and it's part of why I'm posting this on my personal site, not any of my professional sites.
I suspect a conspiracy between Google, and Firefox.
Let's just get something straight that is not common knowledge.
Firefox gets a huge (majority?) chunk of it's funding from Google through it's placement of the search bar and google being the default search agent. Same as you or I would using Google's affiliate search, just ... with a multi million installation user base.
So ... let's get in the other seat
If I was running a top tier company that had conquered search and was now aiming for the heart of the war for the desktop by turning their browser into a full blown opperating system...
What would I do to make sure that people migrated over to my browser before that war took place, so .. I had as big an army as possible before taking the battle field?
Well...
I might go to an existing partner and suggest some form of alliance whereby, the security of their position as the sheperd of open source browsers (and some nice renumeration no doubt) made that partner amenable to introducing small flaws and irritating behaviours, such as to start to migrate people to this "new and improved" browser.
I might for example start making my products work poorly in other browsers and suggest trying my browser instead.
Maybe I'd start introducing crashes more frequently in "that other browser" through my alliance with them.
Maybe some key behaviours like puttin the focus on the URL bar first when opening a new tab would be disrupted.. or other small 'power user' behaviours that helped with irritating the core 'taste makers' to start appreciating those and other UI improvements in my browser.
Now ... I'm not saying anything beyond the fact that I've been more and more irritated using Firefox lately. It crashes more, it's slower than it was, I have constant issues with plugins not being supported anymore ...
And I've been using Chrome a lot more lately.
Just makes you think is all.