Business ethics?

I've just been told by a message on this site that 'my browser is no longer supported,please go to one on the list". My browser is Mozilla Firefox - one of the most popular I believe but not one from the Google/Microsoft stable. I'm not well up on these things but to suddenly decide NOT to support it (I've been in this blog regime with this browser for some years) smells like an unpleasant business practice to me.