Unknown URL dialog doesn't reliably show with multiple UIs

java.lang.UnsupportedOperationException: Not supported yet. com.dmdirc.addons.ui_dummy.DummyController.showURLDialog(DummyController.java:197) com.dmdirc.ui.core.util.URLHandler.launchApp(URLHandler.java:135) com.dmdirc.ui.core.util.URLHandler.launchApp(URLHandler.java:92) com.dmdirc.addons.ui_swing.components.frames.TextFrame.mouseClicked(TextFrame.java:841) com.dmdirc.addons.ui_swing.textpane.TextPaneCanvas.fireMouseEvents(TextPaneCanvas.java:1091) com.dmdirc.addons.ui_swing.textpane.TextPaneCanvas.mouseClicked(TextPaneCanvas.java:475) java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:269) java.awt.Component.processMouseEvent(Component.java:6178) javax.swing.JComponent.processMouseEvent(JComponent.java:3267) java.awt.Component.processEvent(Component.java:5940) java.awt.Container.processEvent(Container.java:2105) java.awt.Component.dispatchEventImpl(Component.java:4536) java.awt.Container.dispatchEventImpl(Container.java:2163) java.awt.Component.dispatchEvent(Component.java:4362) java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4461) java.awt.LightweightDispatcher.processMouseEvent(Container.java:4134) java.awt.LightweightDispatcher.dispatchEvent(Container.java:4055) java.awt.Container.dispatchEventImpl(Container.java:2149) java.awt.Window.dispatchEventImpl(Window.java:2478) java.awt.Component.dispatchEvent(Component.java:4362) java.awt.EventQueue.dispatchEvent(EventQueue.java:604) com.dmdirc.addons.ui_swing.DMDircEventQueue.dispatchEvent(DMDircEventQueue.java:79) java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:275) java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:200) java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190) java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:185) java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:177) java.awt.EventDispatchThread.run(EventDispatchThread.java:138)