Ok, I'm pretty sure this worked before the update, but it came out right before, so I'm not sure. Anyways, the eqn tag doesn't play nicely if there are embedded new lines in the latex. For example this works:
But if I put a line break after the = it displays this:
So not only does it stop it from parsing the latex, it also eats the new line. Not a big deal for simple equations, but for matrix equations it's rather inconvenient.