Hi,
I just encountered a bug in Chrome (possibly other browsers too) leaving 1px trash during 3d animations, like n the attachment.
All you need to do is add 1px border, or box-shadow to the animated element. If you don't want it to be seen - in color of background, or transparent:
border: 1px solid rgba(0,0,0,0);
border: 1px solid transparent;
I hope it'll help someone.
John.