Draggable drifts off axis

Creating a draggable with an axis option ( $( "#divId" ).draggable({axis: 'x'}) )

can cause the draggable element to drift off axis.

For example, suppose one users draggable as the basis for creating a slider.

When using certain rem values defining thumb dimensions (and centering the thumb),

the thumb will drift off-axis on each drag. These errors accumulate as successive drags

are performed.

One possible fix would be to conditionally set top in draggable() _mouseDrag():

_mouseDrag()

...

add this line

if ( o.axis != "x")

this.helper[ 0 ].style.top = this.position.top + "px";

likewise for axis y and left

...

Fiddle Here:

http:jsfiddle.net/e3napvsv/

Buggy behavior shows itself in both Chrome and Firefox.

thanks.