1396
How about no?
(sh.itjust.works)
A place to discuss the news and latest developments on the open-source browser Firefox
It could be they were using new features chrome added which Firefox had as experimental when they wrote it. Firefox recently promoted those features to stable.
It could be but then it's even worse judgement. They basically don't care if Firefox users can view their web site, and that's one thing, but blaming it on Firefox is kind of rich, instead of taking responsibility for their decision. :)