while trying to fix import of javaee-samples I bumped into this happening when running update project configuration.

java.lang.IllegalArgumentException
at org.eclipse.wst.common.project.facet.core.internal.FacetedProjectWorkingCopy.removeProjectFacet(FacetedProjectWorkingCopy.java:876)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject$1.run(FacetedProject.java:309)
at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2313)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject.modify(FacetedProject.java:339)
at org.eclipse.m2e.wtp.WebProjectConfiguratorDelegate.configure(WebProjectConfiguratorDelegate.java:150)
at org.eclipse.m2e.wtp.AbstractProjectConfiguratorDelegate.configureProject(AbstractProjectConfiguratorDelegate.java:93)
at org.eclipse.m2e.wtp.WTPProjectConfigurator.configure(WTPProjectConfigurator.java:70)
at org.eclipse.m2e.core.project.configurator.AbstractLifecycleMapping.configure(AbstractLifecycleMapping.java:120)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager$3.call(ProjectConfigurationManager.java:477)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager$3.call(ProjectConfigurationManager.java:1)
at org.eclipse.m2e.core.internal.embedder.MavenExecutionContext.executeBare(MavenExecutionContext.java:166)
at org.eclipse.m2e.core.internal.embedder.MavenExecutionContext.execute(MavenExecutionContext.java:142)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:470)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager.updateProjectConfiguration0(ProjectConfigurationManager.java:408)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager$2.call(ProjectConfigurationManager.java:321)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager$2.call(ProjectConfigurationManager.java:1)
at org.eclipse.m2e.core.internal.embedder.MavenExecutionContext.executeBare(MavenExecutionContext.java:166)
at org.eclipse.m2e.core.internal.embedder.MavenExecutionContext.execute(MavenExecutionContext.java:142)
at org.eclipse.m2e.core.internal.embedder.MavenExecutionContext.execute(MavenExecutionContext.java:96)
at org.eclipse.m2e.core.internal.embedder.MavenImpl.execute(MavenImpl.java:1344)
at org.eclipse.m2e.core.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:318)
at org.eclipse.m2e.core.ui.internal.UpdateMavenProjectJob.runInWorkspace(UpdateMavenProjectJob.java:77)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:38)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)

It happened on ~100 projects so was quite invasive ;/