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It is possible to stop the event from bubbling further inside a plugin. This means that a plugin can negate an event that should be handled by a different plugin. (Plugin A sends an event (that should be read by Plugin B), Plugin C is listening to this event and stops the event from going further (event.preventDefault()). Because of Plugin C, plugin B never gets the event).
Another alternative
Listen to the window.this.
Consequences
Implementing a central event-bus means that current OSCD plugins need some refactoring to dispatch events to the event-bus instead of dispatching events on itself.
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