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filter is not described

pre_prepare_themes_for_js filter-hook . WP 4.2.0

Filters theme data before it is prepared for JavaScript.

Passing a non-empty array will result in wp_prepare_themes_for_js() returning early with that value instead.

Usage

add_filter( 'pre_prepare_themes_for_js', 'filter_function_name_6728', 10, 3 );
function filter_function_name_6728( $prepared_themes, $themes, $current_theme ){
	// filter...

	return $prepared_themes;
}
$prepared_themes(array)
An associative array of theme data.
Default: empty array
$themes(null/array)
An array of WP_Theme objects to prepare, if any.
$current_theme(string)
The current theme slug.

Where the hook is called

wp_prepare_themes_for_js()
wp-admin/includes/theme.php 536
$prepared_themes = (array) apply_filters( 'pre_prepare_themes_for_js', array(), $themes, $current_theme );

Where the hook is used (in WP core)

Does not used.