When undeploying my ear by removing the ear file from the standalone/deployments folder I sometimes see this exception at the end:

21.06. 16:49:25,674 INFO org.jboss.as.server.deployment#stop WFLYSRV0028: Stopped deployment maj2e-langfr-dev.ear (runtime-name: maj2e-langfr-dev.ear) in 3072ms
21.06. 16:49:26,034 ERROR org.jboss.as.repository#removeContent WFLYDR0010: Couldn't delete content /mbi/tools/jboss/10.0/standalone/data/content/30: java.nio.file.DirectoryNotEmptyException: /mbi/tools/jboss/10.0/standalone/data/content/30
at sun.nio.fs.UnixFileSystemProvider.implDelete(UnixFileSystemProvider.java:242)
at sun.nio.fs.AbstractFileSystemProvider.deleteIfExists(AbstractFileSystemProvider.java:108)
at java.nio.file.Files.deleteIfExists(Files.java:1165)
at org.jboss.as.repository.ContentRepository$Factory$ContentRepositoryImpl.removeContent(ContentRepository.java:370)
at org.jboss.as.server.deployment.DeploymentRemoveHandler$1$1.handleResult(DeploymentRemoveHandler.java:118)
at org.jboss.as.controller.AbstractOperationContext$Step.invokeResultHandler(AbstractOperationContext.java:1420)
at org.jboss.as.controller.AbstractOperationContext$Step.handleResult(AbstractOperationContext.java:1400)
at org.jboss.as.controller.AbstractOperationContext$Step.finalizeInternal(AbstractOperationContext.java:1351)
at org.jboss.as.controller.AbstractOperationContext$Step.finalizeStep(AbstractOperationContext.java:1311)
at org.jboss.as.controller.AbstractOperationContext$Step.access$300(AbstractOperationContext.java:1199)
at org.jboss.as.controller.AbstractOperationContext.finishStep(AbstractOperationContext.java:956)
at org.jboss.as.controller.AbstractOperationContext.executeStep(AbstractOperationContext.java:904)
at org.jboss.as.controller.AbstractOperationContext.doCompleteStep(AbstractOperationContext.java:620)
at org.jboss.as.controller.AbstractOperationContext.completeStepInternal(AbstractOperationContext.java:373)
at org.jboss.as.controller.AbstractOperationContext.executeOperation(AbstractOperationContext.java:349)
at org.jboss.as.controller.OperationContextImpl.executeOperation(OperationContextImpl.java:1201)
at org.jboss.as.controller.ModelControllerImpl.internalExecute(ModelControllerImpl.java:392)
at org.jboss.as.controller.ModelControllerImpl.execute(ModelControllerImpl.java:223)
at org.jboss.as.controller.ModelControllerImpl$3$1$1.run(ModelControllerImpl.java:747)
at org.jboss.as.controller.ModelControllerImpl$3$1$1.run(ModelControllerImpl.java:741)
at java.security.AccessController.doPrivileged(Native Method)
at org.jboss.as.controller.ModelControllerImpl$3$1.run(ModelControllerImpl.java:741)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
at org.jboss.threads.JBossThread.run(JBossThread.java:320)

21.06. 16:49:26,174 INFO org.jboss.as.repository#removeContent WFLYDR0002: Content removed from location /mbi/tools/jboss/10.0/standalone/data/content/30/4fee5b5fa782d2a7f04723ccab3e12351d600b/content
21.06. 16:49:26,176 INFO org.jboss.as.server#handleResult WFLYSRV0009: Undeployed "maj2e-langfr-dev.ear" (runtime-name: "maj2e-langfr-dev.ear")

The exception seems to be ignored. But the named folder and
a file /mbi/tools/jboss/10.0/standalone/data/content/30/7cb1f70d08fb375010369eea154c5db479eaba/content are still there.