I just started testing and using CartoDB, and I am dealing with this problem on a map that has been published already:
I have made minor corrections to the custom HTML infowindow code, and now
a) the infowindows in FF span vertically to the extreme.
b) all layers appear as "visible", even though only 2 of 4 layers should be - in the CartoDB interface, only 2 are visible, the rest is hidden. It also doesn't matter which one.
Maybe the two issues are connected? I have tried lots of refreshing, checking and repasting code, and really don't know a way out.