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action

jetpack_external_storage_init

Fires before the first external storage read. Use this hook to register your storage provider via External_Storage::register_provider(). This fires after the connection package classes are loaded but before any connection status checks read from external storage. Useful for mu-plugins that load before the plugin providing External_Storage, since add_action() does not require the action or any classes to exist at hook-registration time.

Changelog

How to use this hook

See “How to use actions and filters to customize Jetpack”.