org.openjdk.jmc.rjmx.ConnectionException caused by javax.security.sasl.SaslException: org/ietf/jgss/GSSManager [Caused by java.lang.NoClassDefFoundError: org/ietf/jgss/GSSManager]
	at org.openjdk.jmc.rjmx.internal.RJMXConnection.connect(RJMXConnection.java:441)
	at org.openjdk.jmc.rjmx.internal.ServerHandle.doConnect(ServerHandle.java:116)
	at org.openjdk.jmc.rjmx.internal.ServerHandle.connect(ServerHandle.java:100)
	at org.openjdk.jmc.browser.wizards.ConnectionWizardPage$ConnectionTester.run(ConnectionWizardPage.java:792)
	at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:122)
Caused by: javax.security.sasl.SaslException: org/ietf/jgss/GSSManager [Caused by java.lang.NoClassDefFoundError: org/ietf/jgss/GSSManager]
	at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities.handleEvent(ClientConnectionOpenListener.java:425)
	at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities.handleEvent(ClientConnectionOpenListener.java:244)
	at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92)
	at org.xnio.conduits.ReadReadyHandler$ChannelListenerHandler.readReady(ReadReadyHandler.java:66)
	at org.xnio.nio.NioSocketConduit.handleReady(NioSocketConduit.java:89)
	at org.xnio.nio.WorkerThread.run(WorkerThread.java:591)
	at ...asynchronous invocation...(Unknown Source)
	at org.jboss.remoting3.EndpointImpl.connect(EndpointImpl.java:599)
	at org.jboss.remoting3.EndpointImpl.connect(EndpointImpl.java:561)
	at org.jboss.remoting3.EndpointImpl.connect(EndpointImpl.java:549)
	at org.jboss.remotingjmx.RemotingConnector.internalRemotingConnect(RemotingConnector.java:268)
	at org.jboss.remotingjmx.RemotingConnector.internalConnect(RemotingConnector.java:156)
	at org.jboss.remotingjmx.RemotingConnector.connect(RemotingConnector.java:103)
	at org.openjdk.jmc.rjmx.internal.RJMXConnection.connectJmxConnector(RJMXConnection.java:487)
	at org.openjdk.jmc.rjmx.internal.RJMXConnection.establishConnection(RJMXConnection.java:464)
	at org.openjdk.jmc.rjmx.internal.RJMXConnection.connect(RJMXConnection.java:434)
	... 4 more
Caused by: java.lang.NoClassDefFoundError: org/ietf/jgss/GSSManager
	at java.base/java.lang.Class.getDeclaredConstructors0(Native Method)
	at java.base/java.lang.Class.privateGetDeclaredConstructors(Class.java:3137)
	at java.base/java.lang.Class.getConstructor0(Class.java:3342)
	at java.base/java.lang.Class.getConstructor(Class.java:2151)
	at java.base/java.security.Provider.newInstanceUtil(Provider.java:153)
	at java.base/java.security.Provider$Service.newInstance(Provider.java:1818)
	at org.wildfly.security.WildFlyElytronBaseProvider$ProviderService.newInstance(WildFlyElytronBaseProvider.java:218)
	at org.wildfly.security.sasl.util.SecurityProviderSaslClientFactory.createSaslClient(SecurityProviderSaslClientFactory.java:94)
	at org.wildfly.security.sasl.util.AbstractDelegatingSaslClientFactory.createSaslClient(AbstractDelegatingSaslClientFactory.java:66)
	at org.wildfly.security.sasl.util.ProtocolSaslClientFactory.createSaslClient(ProtocolSaslClientFactory.java:50)
	at org.wildfly.security.sasl.util.AbstractDelegatingSaslClientFactory.createSaslClient(AbstractDelegatingSaslClientFactory.java:66)
	at org.wildfly.security.sasl.util.ServerNameSaslClientFactory.createSaslClient(ServerNameSaslClientFactory.java:50)
	at org.wildfly.security.sasl.util.AbstractDelegatingSaslClientFactory.createSaslClient(AbstractDelegatingSaslClientFactory.java:66)
	at org.wildfly.security.sasl.util.ServerNameSaslClientFactory.createSaslClient(ServerNameSaslClientFactory.java:50)
	at org.wildfly.security.sasl.util.FilterMechanismSaslClientFactory.createSaslClient(FilterMechanismSaslClientFactory.java:102)
	at org.wildfly.security.sasl.util.AbstractDelegatingSaslClientFactory.createSaslClient(AbstractDelegatingSaslClientFactory.java:66)
	at org.wildfly.security.sasl.util.LocalPrincipalSaslClientFactory.createSaslClient(LocalPrincipalSaslClientFactory.java:76)
	at org.wildfly.security.sasl.util.PrivilegedSaslClientFactory.lambda$createSaslClient$0(PrivilegedSaslClientFactory.java:64)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at org.wildfly.security.sasl.util.PrivilegedSaslClientFactory.createSaslClient(PrivilegedSaslClientFactory.java:64)
	at org.wildfly.security.auth.client.AuthenticationConfiguration.createSaslClient(AuthenticationConfiguration.java:1545)
	at org.wildfly.security.auth.client.AuthenticationContextConfigurationClient.createSaslClient(AuthenticationContextConfigurationClient.java:430)
	at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities.handleEvent(ClientConnectionOpenListener.java:419)
	at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities.handleEvent(ClientConnectionOpenListener.java:244)
	at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92)
	at org.xnio.conduits.ReadReadyHandler$ChannelListenerHandler.readReady(ReadReadyHandler.java:66)
	at org.xnio.nio.NioSocketConduit.handleReady(NioSocketConduit.java:89)
	at org.xnio.nio.WorkerThread.run(WorkerThread.java:591)

Download and unzip latest WildFly release (Application Server Distribution):
    https://wildfly.org/downloads/

Start the application server:

    cd /path/to/wildfly-20.0.0.Beta1/bin
    ./standalone.sh

Use the latest JDK Mission Control:
    https://github.com/openjdk/jmc
    
Edit '/path/to/jmc/jmc.ini'.
Before the first --add-exports add the following line:
    -Xbootclasspath/a:/path/to/wildfly-20.0.0.Beta1/bin/client/jboss-client.jar

Start JDK Mission Control
    $ /path/to/jmc/jmc

From the menu "File -> Connect -> Create a new connection."
Click on "Custom JMX service URL" and enter the same URL as used in jConsole:
    service:jmx:remote+http://localhost:9990
Click 'Next' which will test the connection

The error above will be seen:
    org.openjdk.jmc.rjmx.ConnectionException caused by javax.security.sasl.SaslException: org/ietf/jgss/GSSManager [Caused by java.lang.NoClassDefFoundError: org/ietf/jgss/GSSManager]
    ....