Blocker Description
Ben says two things need to be looked at: a) does this still exist? b) why does it happen? Do we fix the feature, or do we simply lose the third argument to merge? For alpha: disable third argument. Post-alpha, (potentially) reinstate the third argument. Labelling as P1 because if this merges into "." even when somebody specifies a different location, then it could destroy local mods. Downgrading the priority is fine, once we deal with the location bug (if it truly exists).