Reimplement snapshots of current mapping
Required as mappings might get extended by resources
(from redmine: issue id 1189, created on 2018-09-12tgradl, closed on 2019-05-14)
Required as mappings might get extended by resources
(from redmine: issue id 1189, created on 2018-09-12tgradl, closed on 2019-05-14)