zpool list -v displays invalid EXPANDSZ for unavailable pools
When pools are unavailable their vdevs are also unavailable which means that vdev_max_asize remains at the default zero.
This default was being used to calculate vs_esize resulting in a negative number as vdev_asize > vdev_max_asize, which caused zpool list -v to display 16.0E for EXPANDSZ of these vdevs.
The attached patch from FreeBSD fixes this:
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