Double-clicking on vanilla mugshot doesn't update selection

[focustense]

Currently, the only way to switch to vanilla is to do it the "long" way using the right-side plugin list. Double-clicking on the mugshot does nothing.

This happens because the mod name is a placeholder ("Vanilla") which the model sees as invalid, it can't be resolved and the model won't set it to null.

Either this needs another API (like RevertToVanilla()) or needs a placeholder string to be used when calling SetFaceMod.