Extended the sample to contain test: true

dup.rb

@@ -22,6 +22,7 @@ MAPPINGS = [
 	['stop_grace_period', '--stop-timeout', lambda{|c,i| c.Config.StopTimeout}],
 	['devices', '--device'],
 	['net', '--net'],
+	['ipv6', '--ipv6'],
 	['networks', '--network', lambda{|c,i| c.NetworkSettings.Networks.to_h.keys.map(&:to_s)}, {:type=>:hidden}],
 	['entrypoint', '--entrypoint', lambda{|c,i| (ep=c.Config.Entrypoint) == i.Config.Entrypoint ? nil : ep}, {:allow_empty=>true}],
 	['labels', '--label', lambda{|c,i| l=Hash[c.Config.Labels.to_h.delete_if{|k,v| i.Config.Labels[k]==v rescue false}.map{|k,v| [k.to_s, v]}] ; l}],
@@ -38,6 +39,7 @@ def get_sample(name="container")
 		  image: "my/image:1.2.3"
 		  restart: always
 		  detach: true
+		  test: true # Having this set to true will prevent dup from creating a label de.fabianonline.dup
 		  
 		  ports:
 		    - "1234:1234"