FindingFieldset

This is dispatched when Statamic attemps to find a fieldset for a specific content object.

public function handle(FindingFieldset $event)
{
    $event->data; // The content object. The Page, Entry, etc
    $event->fieldset; // The fieldset.
}

You may modify the fieldset here and it will be reflected in whatever was requesting it.

An example of when this would be useful is to add a section to a fieldset in the publish page on the fly.