(Bug) Edge case: very tall tether objects are not positioned correctly

[NicBright]

I've found an interesting edge case in which the tether object is not positioned correctly:

The edge case concerns only these attachment settings:

• options.attachment: 'bottom left'
• options.attachment: 'bottom right'
• options.attachment: 'bottom center'

The targetAttachment has no effect.

The Bug:

As soon as the tethered element is larger than the available viewport, it seems that tether has the "top" position wrong as if it would only consider the height of the viewport as the height of the tethered element, instead of its actual height.

[TrevorBurnham]

@NicBright Is this still the case in Tether 1.3.1? Can you reproduce in a CodePen?