If I right drag the navbar it copies without issue and I can make it vertical. However, copying either of the navbars produces the error and trying to paste into another web document causes a crash with the attached errors.

I got the usual warnings of link and hover assigned to the same button, but either ignoring or accepting the offer to remove the link made no difference.

As a workaround until something more permanent pops up, why not convert the horizontal to vertical and Save As BBVertical?

(i7, 16GB RAM, GeForce GTX 750 Ti, Win 10 x64) For those looking for hardware comparisons.

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