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action is not described

core_upgrade_preamble action-hook . WP 2.9.0

Fires after the core, plugin, and theme update tables.

Usage

add_action( 'core_upgrade_preamble', 'action_function_name_4187' );
function action_function_name_4187(){
	// action...
}

Changelog

Since 2.9.0 Introduced.

Where the hook is called

In file: /wp-admin/update-core.php
core_upgrade_preamble
wp-admin/update-core.php 785
do_action( 'core_upgrade_preamble' );

Where in WP core the hook is used

Usage not found!