Weld 2.3.5 Weird behaviour

Question

when org.jboss.weld.construction.relaxed=true property added to weld.properties file to WEB-INF directory of a war archive at the deployment this exception is thrown:

10:35:27,762 ERROR [org.jboss.msc.service.fail] (ServerService Thread Pool -- 80) MSC000001: Failed to start service jboss.undertow.deployment.default-server.default-host./test2: org.jboss.msc.service.StartException in service jboss.undertow.deployment.default-server.default-host./test2: java.lang.RuntimeException: java.lang.RuntimeException: java.lang.NullPointerException
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentService$1.run(UndertowDeploymentService.java:85)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)
    at org.jboss.threads.JBossThread.run(JBossThread.java:320)
Caused by: java.lang.RuntimeException: java.lang.RuntimeException: java.lang.NullPointerException
    at io.undertow.servlet.core.DeploymentManagerImpl.deploy(DeploymentManagerImpl.java:236)
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentService.startContext(UndertowDeploymentService.java:100)
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentService$1.run(UndertowDeploymentService.java:82)
    ... 6 more
Caused by: java.lang.RuntimeException: java.lang.NullPointerException
    at com.sun.faces.config.ConfigureListener.contextInitialized(ConfigureListener.java:292)
    at io.undertow.servlet.core.ApplicationListeners.contextInitialized(ApplicationListeners.java:187)
    at io.undertow.servlet.core.DeploymentManagerImpl$1.call(DeploymentManagerImpl.java:200)
    at io.undertow.servlet.core.DeploymentManagerImpl$1.call(DeploymentManagerImpl.java:171)
    at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:42)
    at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.core.DeploymentManagerImpl.deploy(DeploymentManagerImpl.java:234)
    ... 8 more
Caused by: java.lang.NullPointerException
    at com.sun.faces.application.JavaFlowLoaderHelper.loadFlows(JavaFlowLoaderHelper.java:84)
    at com.sun.faces.application.ApplicationAssociate$PostConstructApplicationListener.processEvent(ApplicationAssociate.java:303)
    at javax.faces.event.SystemEvent.processListener(SystemEvent.java:108)
    at com.sun.faces.application.ApplicationImpl.processListeners(ApplicationImpl.java:2169)
    at com.sun.faces.application.ApplicationImpl.invokeListenersFor(ApplicationImpl.java:2142)
    at com.sun.faces.application.ApplicationImpl.publishEvent(ApplicationImpl.java:294)
    at org.jboss.as.jsf.injection.weld.ForwardingApplication.publishEvent(ForwardingApplication.java:294)
    at com.sun.faces.config.ConfigManager.publishPostConfigEvent(ConfigManager.java:704)
    at com.sun.faces.config.ConfigureListener.contextInitialized(ConfigureListener.java:270)
    ... 20 more

which don't say anything meaningful i wonder if that this is expected behavior with bad exception message or a bug because application is working without weld.properties file.

Thanks in advance.