This function had been marked as deprecated since 3.3.0. Use get_current_screen()->add_help_tab()

Add contextual help text for a page.

Creates an ‘Overview’ help tab.

Signature

add_contextual_help( $screen, $help )
screen
 (string) The handle for the screen to add help to. This is usually the hook name returned by the add_*_page() functions.
help
 (string) The content of an 'Overview' help tab.

Return

(void)

Source

function add_contextual_help( $screen, $help ) {
	_deprecated_function( __FUNCTION__, '3.3', 'get_current_screen()->add_help_tab()' );

	if ( is_string( $screen ) )
		$screen = convert_to_screen( $screen );

	WP_Screen::add_old_compat_help( $screen, $help );
}
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