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filter is not described

update_custom_css_data filter-hook . WP 4.7.0

Filters the css (post_content) and preprocessed (post_content_filtered) args for a custom_css post being updated.

This filter can be used by plugin that offer CSS pre-processors, to store the original pre-processed CSS in post_content_filtered and then store processed CSS in post_content. When used in this way, the post_content_filtered should be supplied as the setting value instead of post_content via a the customize_value_custom_css filter, for example:

<code> add_filter( 'customize_value_custom_css', function( $value, $setting ) {

$post = wp_get_custom_css_post( $setting->stylesheet );
if ( $post && ! empty( $post->post_content_filtered ) ) {
	$css = $post->post_content_filtered;
return $css;

}, 10, 2 ); </code>


add_filter( 'update_custom_css_data', 'filter_function_name_6510', 10, 2 );
function filter_function_name_6510( $data, $args ){
	// filter...

	return $data;

Custom CSS data.

  • $css (string)
    CSS stored in post_content.

  • $preprocessed (string)
    Pre-processed CSS stored in post_content_filtered. Normally empty string.

The args passed into wp_update_custom_css_post() merged with defaults.

  • $css (string)
    The original CSS passed in to be updated.

  • $preprocessed (string)
    The original preprocessed CSS passed in to be updated.

  • $stylesheet (string)
    The stylesheet (theme) being updated.


Since 4.7.0 Introduced.

Where the hook is called

wp-includes/theme.php 1884
$data = apply_filters( 'update_custom_css_data', $data, array_merge( $args, compact( 'css' ) ) );

Where in WP core the hook is used

Usage not found!