Documented at https://github.com/folio-org/stripes-core/blob/master/doc/dev-guide.md#modules

Fixed in https://github.com/folio-org/stripes-core/commit/fa75ed72cd6cce2cae14971262d266b45af9952f

Updates to documentation still to follow before I close this.

A dynamic solution for this is becoming more urgent as we begin to add additional settings into the system. Settings in stripes-core now attempts to load settings from both ui-users and ui-items. If either one of those is missing, the whole UI crashes.