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action is not described

welcome_panel action-hook . WP 3.5.0

Add content to the welcome panel on the admin dashboard.

To remove the default welcome panel, use remove_action():

remove_action( 'welcome_panel', 'wp_welcome_panel' );

Usage

add_action( 'welcome_panel', 'action_function_name_3398' );
function action_function_name_3398(){
	// action...
}

Where the hook is called

In file: /wp-admin/index.php
welcome_panel
wp-admin/index.php 175
do_action( 'welcome_panel' );

Where in WP core the hook is used WordPress

wp-includes/default-filters.php 409
add_action( 'welcome_panel', 'wp_welcome_panel' );