org.jboss.weld.tests.specialization.ExtSpecializationTest already covers a scenario with indirect (transitive) specialization and passes.
I added org.jboss.weld.tests.specialization.MultipleSpecializationTest (see https://github.com/bafco/core/commits/WELD-1562) that tests also the invocation of methods of the specializing class and it passes too.

However, with Jetty, a proxy for BeanB is created instead of BeanC and the following error occurs:

javax.el.ELException: /views/index.xhtml: The class 'test.BeanB$Proxy$_$$_WeldClientProxy' does not have the property 'propC'.
	at com.sun.faces.facelets.compiler.TextInstruction.write(TextInstruction.java:88)
	at com.sun.faces.facelets.compiler.UIInstructions.encodeBegin(UIInstructions.java:82)
	at com.sun.faces.facelets.compiler.UILeaf.encodeAll(UILeaf.java:207)
	at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1822)
	at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1822)
	at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:447)
	at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:124)
	at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:286)
	at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:286)
	at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120)
	at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
	at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
	at org.apache.deltaspike.jsf.impl.listener.request.DeltaSpikeLifecycleWrapper.render(DeltaSpikeLifecycleWrapper.java:97)
	at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:698)
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:505)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:138)
	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:582)
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:213)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1096)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:432)
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:175)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1030)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:136)
	at org.eclipse.jetty.server.Dispatcher.forward(Dispatcher.java:261)
	at org.eclipse.jetty.server.Dispatcher.forward(Dispatcher.java:101)
	at org.eclipse.jetty.servlet.DefaultServlet.doGet(DefaultServlet.java:546)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:735)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:848)
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:698)
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:505)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:138)
	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:564)
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:213)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1096)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:432)
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:175)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1030)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:136)
	at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:201)
	at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:109)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
	at org.eclipse.jetty.server.Server.handle(Server.java:445)
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:268)
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:229)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.run(AbstractConnection.java:358)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:601)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:532)
	at java.lang.Thread.run(Thread.java:722)

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