[Pharo-project] Question: How can I add a items to System Browser Window menu?

Hello! I want to add an item to the menu that appears when you right click on a category in the System Browser window. I think that menu is built here: Morph>>buildMetaMenu: evt But I don't want to touch that method, not SystemWindow>>buildMetaMenu: evt either, because that option would have to be visible only if my project has been loaded. Is there a way to do that? Thanks! Carla