Oh! That's nasty.
It also seems to affect Chrome and Safari on the PC.
And, come to think of it, I've been experiencing some weird behaviour from one of my Chrome extensions in conjunction with jQuery lately.
Maybe this has got something to do with it.
Anyway, as this is a regression from 1.8.3, you can just drop back to that version by way of a workaround until they fix the problem.
Or, if you absolutely need to use the latest version, just do:
$('body').removeAttr( 'style' );