This event is emitted before an [up-defer] placeholder loads its deferred content.
[up-defer]
The event can be prevented to stop the network request. The loading will not be attempted again, but you can use up.deferred.load() to manually load afterwards.
up.deferred.load()
Lazy loading content
The [up-defer] placeholder that is about to load its content.
An object with render options for the coming fragment update.
Listeners may inspect and modify these options.
Prevents the deferred content from being loaded.
