I have a Jenkinsfile that i have been using for several months.
After upgrading from version 4340 to 4349 there seem to have been a regression where i now get a error on the one job where i use fsGroup

This can be seen here:

https://github.com/SimonStiil/kube-auth-proxy/blob/main/Jenkinsfile#L78

this results in the following error:

 
java.lang.NullPointerException
Caused: com.fasterxml.jackson.databind.JsonMappingException: (was java.lang.NullPointerException) (through reference chain: io.fabric8.kubernetes.api.model.Pod["spec"]>io.fabric8.kubernetes.api.model.PodSpec["containers"]>java.util.ArrayList[3]>io.fabric8.kubernetes.api.model.Container["securityContext"]>io.fabric8.kubernetes.api.model.SecurityContext["getAdditionalProperties"]->java.util.LinkedHashMap["fsGroup"])
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:400)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:359)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.std.StdSerializer.wrapAndThrow(StdSerializer.java:324)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.std.MapSerializer.serializeFields(MapSerializer.java:810)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.std.MapSerializer.serializeWithoutTypeInfo(MapSerializer.java:763)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.AnyGetterWriter.getAndSerialize(AnyGetterWriter.java:81)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.AnyGetterWriter.serializeAsField(AnyGetterWriter.java:89)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.model.jackson.BeanPropertyWriterDelegate.serializeAsField(BeanPropertyWriterDelegate.java:68)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:760)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.model.jackson.BeanPropertyWriterDelegate.serializeAsField(BeanPropertyWriterDelegate.java:68)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:760)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.impl.IndexedListSerializer.serializeContents(IndexedListSerializer.java:119)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.impl.IndexedListSerializer.serialize(IndexedListSerializer.java:79)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.impl.IndexedListSerializer.serialize(IndexedListSerializer.java:18)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.model.jackson.BeanPropertyWriterDelegate.serializeAsField(BeanPropertyWriterDelegate.java:68)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:760)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.model.jackson.BeanPropertyWriterDelegate.serializeAsField(BeanPropertyWriterDelegate.java:68)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:760)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:503)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:342)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ObjectMapper._writeValueAndClose(ObjectMapper.java:4859)
at PluginClassLoader for jackson2-api//com.fasterxml.jackson.databind.ObjectMapper.writeValueAsString(ObjectMapper.java:4079)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.utils.KubernetesSerialization.asJson(KubernetesSerialization.java:169)
Caused: io.fabric8.kubernetes.client.KubernetesClientException: An error has occurred.
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.KubernetesClientException.launderThrowable(KubernetesClientException.java:129)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.KubernetesClientException.launderThrowable(KubernetesClientException.java:122)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.utils.KubernetesSerialization.asJson(KubernetesSerialization.java:171)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.dsl.internal.OperationSupport.handleCreate(OperationSupport.java:338)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.dsl.internal.BaseOperation.handleCreate(BaseOperation.java:753)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.dsl.internal.BaseOperation.handleCreate(BaseOperation.java:97)
at PluginClassLoader for kubernetes-client-api//io.fabric8.kubernetes.client.dsl.internal.CreateOnlyResourceOperation.create(CreateOnlyResourceOperation.java:42)
at PluginClassLoader for kubernetes//org.csanchez.jenkins.plugins.kubernetes.KubernetesLauncher.launch(KubernetesLauncher.java:164)
at hudson.slaves.SlaveComputer.lambda$_connect$0(SlaveComputer.java:297)
at jenkins.util.ContextResettingExecutorService$2.call(ContextResettingExecutorService.java:46)
at jenkins.security.ImpersonatingExecutorService$2.call(ImpersonatingExecutorService.java:80)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.base/java.lang.Thread.run(Unknown Source)