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.
I'm glad the ceo at the time was wise enough to recognize what she had and made the os open source, and still somehow managed to sell it in the end. Web os lives on tvs now, although many of it's benefits are wasted there.