Today 10 years ago I went to Poland to buy a Phone with pre installed #Firefox OS on. The Phone was a Alcatel One, so very shitty. Two years later I installed Firefox OS on my Nexus 5 instead.
It was a very good concept, but sadly rolled out on too shitty hardware so it never caught on.
Facebook has phones too back then, though they're just Android with Facebook button.
Not long before Amazon came out with their spyware phone.
Seriously - they bragged about how the Fire Phone was always spying on you and still tried to charge $600 for it. Like three months later, they had to discount it to $99 and include a year of Prime.