1) Create new JSF kick start Project with Facelets
2) Open greeting.xhtml with JBossTools editor
3) Try to make Open-On on a "/templates/common.xhtml" link

RESULT: Nothing. Open-On doesn't work.

The possible reason is a conflict with Doxia Xhtml Editor. When we try to make Open-On in this editor an exception is thrown:

java.lang.AbstractMethodError
at org.eclipse.mylyn.internal.tasks.ui.TasksUiPlugin$11.run(TasksUiPlugin.java:1164)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.runtime.Platform.run(Platform.java:888)
at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:48)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
at org.eclipse.mylyn.internal.tasks.ui.TasksUiPlugin.getRepositoryForResource(TasksUiPlugin.java:1157)
at org.eclipse.mylyn.tasks.ui.AbstractTaskHyperlinkDetector.getTaskRepository(AbstractTaskHyperlinkDetector.java:166)
at org.eclipse.mylyn.tasks.ui.AbstractTaskHyperlinkDetector.getTaskRepositories(AbstractTaskHyperlinkDetector.java:130)
at org.eclipse.mylyn.internal.tasks.ui.editors.TaskHyperlinkDetector.detectHyperlinks(TaskHyperlinkDetector.java:38)
at org.eclipse.mylyn.tasks.ui.AbstractTaskHyperlinkDetector.detectHyperlinks(AbstractTaskHyperlinkDetector.java:93)
at org.eclipse.ui.texteditor.HyperlinkDetectorRegistry$HyperlinkDetectorDelegate.detectHyperlinks(HyperlinkDetectorRegistry.java:80)
at org.eclipse.jface.text.hyperlink.HyperlinkManager.findHyperlinks(HyperlinkManager.java:263)
at org.eclipse.jface.text.hyperlink.HyperlinkManager.mouseMove(HyperlinkManager.java:439)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:199)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3880)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3473)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2405)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2369)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2221)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:500)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:493)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:194)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:368)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:559)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:514)
at org.eclipse.equinox.launcher.Main.run(Main.java:1311)
at org.eclipse.equinox.launcher.Main.main(Main.java:1287)