PharoLauncher is currently leaking AnnouncementSubscriptions when its window closes. I'm not sure with Spec how to ensure actions are performed when the window is closed, but I have been able to achieve this with the following modification [1] which is... ----- WindowModel>>windowIsClosing isClosedHolder value: true self model windowIsClosing "<----proposed modification" ----- I investigated with a halt in SpecWindow>>close to trace through and discover that it calls... SpecWindow(StandardWindow)>>delete, which in my non-fullscreen-case calls... SpecWindow(SystemWindow)>>delete, which "model windowIsClosing" calls... MorphicWindowAdaptor>>windowIsClosing, which "self model windowIsClosing" calls... WindowModel>>windowIsClosing, which does only "isClosedHolder value: true" That last line happens to hold aPharoLauncher in its 'model' instance variable, so with the above proposal I can implement PharoLauncher>>windowIsClosing to unregister the announcer. Any problem expected with that modification? [1] https://pharo.fogbugz.com/f/cases/12677 cheers -ben