Quote from gamemaster128@Decabah
It's probably due to a conflicting addon. Try disabling your addons in batches until the error goes away and then narrow it down further by enabling a few of the addons you just previously disabled until the error returns.
I did that before reporting it and no dice. I did find a conflict between two other addons that was borking a frame up, so that's good, but nothing to do with Skinner.