How to reproduce :

• create a myfavorite content with tow links, then add a new link between the first and the second one.
• save
  > an error occured

  java.util.ArrayList cannot be cast to java.lang.String
  java.lang.ClassCastException: java.util.ArrayList cannot be cast to java.lang.String
      at org.ametys.cms.workflow.EditContentFunction._bindAndValidateRepeater(EditContentFunction.java:983)
      at org.ametys.cms.workflow.EditContentFunction._bindAndValidateCompositeMetadata(EditContentFunction.java:924)
      at org.ametys.cms.workflow.EditContentFunction._bindAndValidateMetadata(EditContentFunction.java:807)
      at org.ametys.cms.workflow.EditContentFunction._bindAndValidateMetadataSetElement(EditContentFunction.java:591)
      at org.ametys.cms.workflow.EditContentFunction._bindAndValidateContent(EditContentFunction.java:542)
      at org.ametys.cms.workflow.EditContentFunction.execute(EditContentFunction.java:307)
      at sun.reflect.GeneratedMethodAccessor132.invoke(Unknown Source)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:483)
      at org.ametys.runtime.plugin.component.PluginsComponentManager$ComponentInvocationHandler.invoke(PluginsComponentManager.java:177)
      at com.sun.proxy.$Proxy33.execute(Unknown Source)
      at com.opensymphony.workflow.AbstractWorkflow.executeFunction(AbstractWorkflow.java:871)
      at com.opensymphony.workflow.AbstractWorkflow.transitionWorkflow(AbstractWorkflow.java:1044)
      at org.ametys.plugins.workflow.AbstractAmetysWorkflow.transitionWorkflow(AbstractAmetysWorkflow.java:209)
      at com.opensymphony.workflow.AbstractWorkflow.doAction(AbstractWorkflow.java:567)
      at org.ametys.plugins.workflow.AbstractAmetysWorkflow.doAction(AbstractAmetysWorkflow.java:164)
      at org.ametys.cms.workflow.ContentWorkflowAction._act(ContentWorkflowAction.java:69)
      at org.ametys.plugins.workflow.cocoon.AbstractWorkflowAction.act(AbstractWorkflowAction.java:71)
      at org.apache.cocoon.components.treeprocessor.sitemap.ActTypeNode.invoke(ActTypeNode.java:125)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
      at org.apache.cocoon.components.treeprocessor.sitemap.ActTypeNode.invoke(ActTypeNode.java:139)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
      at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.buildPipeline(ConcreteTreeProcessor.java:194)
      at org.apache.cocoon.components.treeprocessor.TreeProcessor.buildPipeline(TreeProcessor.java:267)
      at org.apache.cocoon.components.treeprocessor.sitemap.MountNode.invoke(MountNode.java:111)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
      at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.buildPipeline(ConcreteTreeProcessor.java:194)
      at org.apache.cocoon.components.treeprocessor.TreeProcessor.buildPipeline(TreeProcessor.java:267)
      at org.apache.cocoon.components.source.impl.SitemapSource.init(SitemapSource.java:333)
      at org.apache.cocoon.components.source.impl.SitemapSource.<init>(SitemapSource.java:215)
      at org.apache.cocoon.components.source.impl.SitemapSourceFactory.getSource(SitemapSourceFactory.java:68)
      at org.apache.excalibur.source.impl.SourceResolverImpl.resolveURI(SourceResolverImpl.java:208)
      at org.apache.cocoon.components.CocoonComponentManager.resolveURI(CocoonComponentManager.java:558)
      at org.apache.cocoon.components.CocoonComponentManager.resolveURI(CocoonComponentManager.java:558)
      at org.apache.cocoon.components.CocoonComponentManager.resolveURI(CocoonComponentManager.java:558)
      at org.apache.cocoon.components.CocoonComponentManager.resolveURI(CocoonComponentManager.java:558)
      at org.ametys.core.ui.dispatcher.DispatchGenerator._dispatching(DispatchGenerator.java:139)
      at org.ametys.core.ui.dispatcher.DispatchGenerator.generate(DispatchGenerator.java:88)
      at org.apache.cocoon.components.pipeline.AbstractProcessingPipeline.processXMLPipeline(AbstractProcessingPipeline.java:581)
      at org.apache.cocoon.components.pipeline.impl.AbstractCachingProcessingPipeline.processXMLPipeline(AbstractCachingProcessingPipeline.java:301)
      at org.apache.cocoon.components.pipeline.AbstractProcessingPipeline.process(AbstractProcessingPipeline.java:483)
      at org.apache.cocoon.components.treeprocessor.sitemap.SerializeNode.invoke(SerializeNode.java:144)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
      at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:178)
      at org.apache.cocoon.components.treeprocessor.TreeProcessor.process(TreeProcessor.java:254)
      at org.apache.cocoon.components.treeprocessor.sitemap.MountNode.invoke(MountNode.java:118)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
      at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:178)
      at org.apache.cocoon.components.treeprocessor.TreeProcessor.process(TreeProcessor.java:254)
      at org.apache.cocoon.components.treeprocessor.sitemap.MountNode.invoke(MountNode.java:118)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
      at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:178)
      at org.apache.cocoon.components.treeprocessor.TreeProcessor.process(TreeProcessor.java:254)
      at org.apache.cocoon.components.treeprocessor.sitemap.MountNode.invoke(MountNode.java:118)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
      at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
      at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
      at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
      at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:178)
      at org.apache.cocoon.components.treeprocessor.TreeProcessor.process(TreeProcessor.java:254)
      at org.apache.cocoon.Cocoon.process(Cocoon.java:699)
      at org.ametys.runtime.servlet.RuntimeServlet.service(RuntimeServlet.java:542)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
      at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
      at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
      at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:617)
      at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
      at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
      at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
      at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
      at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2463)
      at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2452)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
      at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
      at java.lang.Thread.run(Thread.java:745)