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Also, since addons are not extending from a HTMLElement, addons cannot subscribe to events themselves. HTML events are only going upwards in the DOMTree, not downwards and/or to siblings.
Pros/Cons
Decision
If we want plug-ins for OpenSCD to be asynchronous accessible to each other, OpenSCD-Core should make use of a central event-bus.
Instead of dispatching an event on the plug-in itself, the plug-in can dispatch an event on the central event-bus.
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