Merge pull request #449 from greboid/master

Fix systray plugin

systray/src/com/dmdirc/addons/systray/SystrayManager.java

 
 import com.dmdirc.ClientModule.GlobalConfig;
 import com.dmdirc.DMDircMBassador;
+import com.dmdirc.addons.ui_swing.EdtHandlerInvocation;
 import com.dmdirc.addons.ui_swing.MainFrame;
 import com.dmdirc.config.prefs.PluginPreferencesCategory;
 import com.dmdirc.config.prefs.PreferencesCategory;
         }
     }
 
-    @Handler
+    @Handler(invocation = EdtHandlerInvocation.class)
     public void handleClientMinimised(final ClientMinimisedEvent event) {
         if (globalConfig.getOptionBool(domain, "autominimise")) {
             mainFrame.setVisible(false);