Posted when the MPF-MC is available to start showing slides and playing sounds.
Note that this event does not mean the MC is done loading. Instead it’s posted at the earliest possible moment that the core MC components are available, meaning you can trigger “boot” slides from this event (which could in turn be used to show asset loading status, boot progress, etc.)
If you want to show slides that require images or video loaded from disk, use the event “init_done” instead which is posted once all the assets set to “preload” have been loaded.
This event does not have any keyword arguments