| ⇢ | A | ListenerData added | |
| B | ↘ | C | Environment got worse |
| ⇢ | A | Environment::getListenersForEvent() added | |
| ⇢ | A | ListenerData::__construct() added | |
| ⇢ | A | ListenerData::getListener() added | |
| ⇢ | A | ListenerData::getEvent() added | |
| ⇢ | A | Environment::setEventDispatcher() added |