Adding upstream version 6.4.3+dfsg1.upstream/6.4.3+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2046 insertions, 0 deletions

diff --git a/wp-includes/blocks.php b/wp-includes/blocks.php
new file mode 100644
index 0000000..34ff3a2
--- /dev/null
+++ b/wp-includes/blocks.php
@@ -0,0 +1,2046 @@
+<?php
+/**
+ * Functions related to registering and parsing blocks.
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ * @since 5.0.0
+ */
+
+/**
+ * Removes the block asset's path prefix if provided.
+ *
+ * @since 5.5.0
+ *
+ * @param string $asset_handle_or_path Asset handle or prefixed path.
+ * @return string Path without the prefix or the original value.
+ */
+function remove_block_asset_path_prefix( $asset_handle_or_path ) {
+	$path_prefix = 'file:';
+	if ( ! str_starts_with( $asset_handle_or_path, $path_prefix ) ) {
+		return $asset_handle_or_path;
+	}
+	$path = substr(
+		$asset_handle_or_path,
+		strlen( $path_prefix )
+	);
+	if ( str_starts_with( $path, './' ) ) {
+		$path = substr( $path, 2 );
+	}
+	return $path;
+}
+
+/**
+ * Generates the name for an asset based on the name of the block
+ * and the field name provided.
+ *
+ * @since 5.5.0
+ * @since 6.1.0 Added `$index` parameter.
+ *
+ * @param string $block_name Name of the block.
+ * @param string $field_name Name of the metadata field.
+ * @param int    $index      Optional. Index of the asset when multiple items passed.
+ *                           Default 0.
+ * @return string Generated asset name for the block's field.
+ */
+function generate_block_asset_handle( $block_name, $field_name, $index = 0 ) {
+	if ( str_starts_with( $block_name, 'core/' ) ) {
+		$asset_handle = str_replace( 'core/', 'wp-block-', $block_name );
+		if ( str_starts_with( $field_name, 'editor' ) ) {
+			$asset_handle .= '-editor';
+		}
+		if ( str_starts_with( $field_name, 'view' ) ) {
+			$asset_handle .= '-view';
+		}
+		if ( $index > 0 ) {
+			$asset_handle .= '-' . ( $index + 1 );
+		}
+		return $asset_handle;
+	}
+
+	$field_mappings = array(
+		'editorScript' => 'editor-script',
+		'script'       => 'script',
+		'viewScript'   => 'view-script',
+		'editorStyle'  => 'editor-style',
+		'style'        => 'style',
+	);
+	$asset_handle   = str_replace( '/', '-', $block_name ) .
+		'-' . $field_mappings[ $field_name ];
+	if ( $index > 0 ) {
+		$asset_handle .= '-' . ( $index + 1 );
+	}
+	return $asset_handle;
+}
+
+/**
+ * Gets the URL to a block asset.
+ *
+ * @since 6.4.0
+ *
+ * @param string $path A normalized path to a block asset.
+ * @return string|false The URL to the block asset or false on failure.
+ */
+function get_block_asset_url( $path ) {
+	if ( empty( $path ) ) {
+		return false;
+	}
+
+	// Path needs to be normalized to work in Windows env.
+	static $wpinc_path_norm = '';
+	if ( ! $wpinc_path_norm ) {
+		$wpinc_path_norm = wp_normalize_path( realpath( ABSPATH . WPINC ) );
+	}
+
+	if ( str_starts_with( $path, $wpinc_path_norm ) ) {
+		return includes_url( str_replace( $wpinc_path_norm, '', $path ) );
+	}
+
+	static $template_paths_norm = array();
+
+	$template = get_template();
+	if ( ! isset( $template_paths_norm[ $template ] ) ) {
+		$template_paths_norm[ $template ] = wp_normalize_path( get_template_directory() );
+	}
+
+	if ( str_starts_with( $path, trailingslashit( $template_paths_norm[ $template ] ) ) ) {
+		return get_theme_file_uri( str_replace( $template_paths_norm[ $template ], '', $path ) );
+	}
+
+	if ( is_child_theme() ) {
+		$stylesheet = get_stylesheet();
+		if ( ! isset( $template_paths_norm[ $stylesheet ] ) ) {
+			$template_paths_norm[ $stylesheet ] = wp_normalize_path( get_stylesheet_directory() );
+		}
+
+		if ( str_starts_with( $path, trailingslashit( $template_paths_norm[ $stylesheet ] ) ) ) {
+			return get_theme_file_uri( str_replace( $template_paths_norm[ $stylesheet ], '', $path ) );
+		}
+	}
+
+	return plugins_url( basename( $path ), $path );
+}
+
+/**
+ * Finds a script handle for the selected block metadata field. It detects
+ * when a path to file was provided and finds a corresponding asset file
+ * with details necessary to register the script under automatically
+ * generated handle name. It returns unprocessed script handle otherwise.
+ *
+ * @since 5.5.0
+ * @since 6.1.0 Added `$index` parameter.
+ *
+ * @param array  $metadata   Block metadata.
+ * @param string $field_name Field name to pick from metadata.
+ * @param int    $index      Optional. Index of the script to register when multiple items passed.
+ *                           Default 0.
+ * @return string|false Script handle provided directly or created through
+ *                      script's registration, or false on failure.
+ */
+function register_block_script_handle( $metadata, $field_name, $index = 0 ) {
+	if ( empty( $metadata[ $field_name ] ) ) {
+		return false;
+	}
+
+	$script_handle = $metadata[ $field_name ];
+	if ( is_array( $script_handle ) ) {
+		if ( empty( $script_handle[ $index ] ) ) {
+			return false;
+		}
+		$script_handle = $script_handle[ $index ];
+	}
+
+	$script_path = remove_block_asset_path_prefix( $script_handle );
+	if ( $script_handle === $script_path ) {
+		return $script_handle;
+	}
+
+	$path                  = dirname( $metadata['file'] );
+	$script_asset_raw_path = $path . '/' . substr_replace( $script_path, '.asset.php', - strlen( '.js' ) );
+	$script_handle         = generate_block_asset_handle( $metadata['name'], $field_name, $index );
+	$script_asset_path     = wp_normalize_path(
+		realpath( $script_asset_raw_path )
+	);
+
+	if ( empty( $script_asset_path ) ) {
+		_doing_it_wrong(
+			__FUNCTION__,
+			sprintf(
+				/* translators: 1: Asset file location, 2: Field name, 3: Block name.  */
+				__( 'The asset file (%1$s) for the "%2$s" defined in "%3$s" block definition is missing.' ),
+				$script_asset_raw_path,
+				$field_name,
+				$metadata['name']
+			),
+			'5.5.0'
+		);
+		return false;
+	}
+
+	$script_path_norm = wp_normalize_path( realpath( $path . '/' . $script_path ) );
+	$script_uri       = get_block_asset_url( $script_path_norm );
+
+	$script_args = array();
+	if ( 'viewScript' === $field_name && $script_uri ) {
+		$script_args['strategy'] = 'defer';
+	}
+
+	$script_asset        = require $script_asset_path;
+	$script_dependencies = isset( $script_asset['dependencies'] ) ? $script_asset['dependencies'] : array();
+	$result              = wp_register_script(
+		$script_handle,
+		$script_uri,
+		$script_dependencies,
+		isset( $script_asset['version'] ) ? $script_asset['version'] : false,
+		$script_args
+	);
+	if ( ! $result ) {
+		return false;
+	}
+
+	if ( ! empty( $metadata['textdomain'] ) && in_array( 'wp-i18n', $script_dependencies, true ) ) {
+		wp_set_script_translations( $script_handle, $metadata['textdomain'] );
+	}
+
+	return $script_handle;
+}
+
+/**
+ * Finds a style handle for the block metadata field. It detects when a path
+ * to file was provided and registers the style under automatically
+ * generated handle name. It returns unprocessed style handle otherwise.
+ *
+ * @since 5.5.0
+ * @since 6.1.0 Added `$index` parameter.
+ *
+ * @param array  $metadata   Block metadata.
+ * @param string $field_name Field name to pick from metadata.
+ * @param int    $index      Optional. Index of the style to register when multiple items passed.
+ *                           Default 0.
+ * @return string|false Style handle provided directly or created through
+ *                      style's registration, or false on failure.
+ */
+function register_block_style_handle( $metadata, $field_name, $index = 0 ) {
+	if ( empty( $metadata[ $field_name ] ) ) {
+		return false;
+	}
+
+	$style_handle = $metadata[ $field_name ];
+	if ( is_array( $style_handle ) ) {
+		if ( empty( $style_handle[ $index ] ) ) {
+			return false;
+		}
+		$style_handle = $style_handle[ $index ];
+	}
+
+	$style_handle_name = generate_block_asset_handle( $metadata['name'], $field_name, $index );
+	// If the style handle is already registered, skip re-registering.
+	if ( wp_style_is( $style_handle_name, 'registered' ) ) {
+		return $style_handle_name;
+	}
+
+	static $wpinc_path_norm = '';
+	if ( ! $wpinc_path_norm ) {
+		$wpinc_path_norm = wp_normalize_path( realpath( ABSPATH . WPINC ) );
+	}
+
+	$is_core_block = isset( $metadata['file'] ) && str_starts_with( $metadata['file'], $wpinc_path_norm );
+	// Skip registering individual styles for each core block when a bundled version provided.
+	if ( $is_core_block && ! wp_should_load_separate_core_block_assets() ) {
+		return false;
+	}
+
+	$style_path      = remove_block_asset_path_prefix( $style_handle );
+	$is_style_handle = $style_handle === $style_path;
+	// Allow only passing style handles for core blocks.
+	if ( $is_core_block && ! $is_style_handle ) {
+		return false;
+	}
+	// Return the style handle unless it's the first item for every core block that requires special treatment.
+	if ( $is_style_handle && ! ( $is_core_block && 0 === $index ) ) {
+		return $style_handle;
+	}
+
+	// Check whether styles should have a ".min" suffix or not.
+	$suffix = SCRIPT_DEBUG ? '' : '.min';
+	if ( $is_core_block ) {
+		$style_path = ( 'editorStyle' === $field_name ) ? "editor{$suffix}.css" : "style{$suffix}.css";
+	}
+
+	$style_path_norm = wp_normalize_path( realpath( dirname( $metadata['file'] ) . '/' . $style_path ) );
+	$style_uri       = get_block_asset_url( $style_path_norm );
+
+	$version = ! $is_core_block && isset( $metadata['version'] ) ? $metadata['version'] : false;
+	$result  = wp_register_style(
+		$style_handle_name,
+		$style_uri,
+		array(),
+		$version
+	);
+	if ( ! $result ) {
+		return false;
+	}
+
+	if ( $style_uri ) {
+		wp_style_add_data( $style_handle_name, 'path', $style_path_norm );
+
+		if ( $is_core_block ) {
+			$rtl_file = str_replace( "{$suffix}.css", "-rtl{$suffix}.css", $style_path_norm );
+		} else {
+			$rtl_file = str_replace( '.css', '-rtl.css', $style_path_norm );
+		}
+
+		if ( is_rtl() && file_exists( $rtl_file ) ) {
+			wp_style_add_data( $style_handle_name, 'rtl', 'replace' );
+			wp_style_add_data( $style_handle_name, 'suffix', $suffix );
+			wp_style_add_data( $style_handle_name, 'path', $rtl_file );
+		}
+	}
+
+	return $style_handle_name;
+}
+
+/**
+ * Gets i18n schema for block's metadata read from `block.json` file.
+ *
+ * @since 5.9.0
+ *
+ * @return object The schema for block's metadata.
+ */
+function get_block_metadata_i18n_schema() {
+	static $i18n_block_schema;
+
+	if ( ! isset( $i18n_block_schema ) ) {
+		$i18n_block_schema = wp_json_file_decode( __DIR__ . '/block-i18n.json' );
+	}
+
+	return $i18n_block_schema;
+}
+
+/**
+ * Registers a block type from the metadata stored in the `block.json` file.
+ *
+ * @since 5.5.0
+ * @since 5.7.0 Added support for `textdomain` field and i18n handling for all translatable fields.
+ * @since 5.9.0 Added support for `variations` and `viewScript` fields.
+ * @since 6.1.0 Added support for `render` field.
+ * @since 6.3.0 Added `selectors` field.
+ * @since 6.4.0 Added support for `blockHooks` field.
+ *
+ * @param string $file_or_folder Path to the JSON file with metadata definition for
+ *                               the block or path to the folder where the `block.json` file is located.
+ *                               If providing the path to a JSON file, the filename must end with `block.json`.
+ * @param array  $args           Optional. Array of block type arguments. Accepts any public property
+ *                               of `WP_Block_Type`. See WP_Block_Type::__construct() for information
+ *                               on accepted arguments. Default empty array.
+ * @return WP_Block_Type|false The registered block type on success, or false on failure.
+ */
+function register_block_type_from_metadata( $file_or_folder, $args = array() ) {
+	/*
+	 * Get an array of metadata from a PHP file.
+	 * This improves performance for core blocks as it's only necessary to read a single PHP file
+	 * instead of reading a JSON file per-block, and then decoding from JSON to PHP.
+	 * Using a static variable ensures that the metadata is only read once per request.
+	 */
+	static $core_blocks_meta;
+	if ( ! $core_blocks_meta ) {
+		$core_blocks_meta = require ABSPATH . WPINC . '/blocks/blocks-json.php';
+	}
+
+	$metadata_file = ( ! str_ends_with( $file_or_folder, 'block.json' ) ) ?
+		trailingslashit( $file_or_folder ) . 'block.json' :
+		$file_or_folder;
+
+	$is_core_block = str_starts_with( $file_or_folder, ABSPATH . WPINC );
+
+	if ( ! $is_core_block && ! file_exists( $metadata_file ) ) {
+		return false;
+	}
+
+	// Try to get metadata from the static cache for core blocks.
+	$metadata = false;
+	if ( $is_core_block ) {
+		$core_block_name = str_replace( ABSPATH . WPINC . '/blocks/', '', $file_or_folder );
+		if ( ! empty( $core_blocks_meta[ $core_block_name ] ) ) {
+			$metadata = $core_blocks_meta[ $core_block_name ];
+		}
+	}
+
+	// If metadata is not found in the static cache, read it from the file.
+	if ( ! $metadata ) {
+		$metadata = wp_json_file_decode( $metadata_file, array( 'associative' => true ) );
+	}
+
+	if ( ! is_array( $metadata ) || empty( $metadata['name'] ) ) {
+		return false;
+	}
+	$metadata['file'] = wp_normalize_path( realpath( $metadata_file ) );
+
+	/**
+	 * Filters the metadata provided for registering a block type.
+	 *
+	 * @since 5.7.0
+	 *
+	 * @param array $metadata Metadata for registering a block type.
+	 */
+	$metadata = apply_filters( 'block_type_metadata', $metadata );
+
+	// Add `style` and `editor_style` for core blocks if missing.
+	if ( ! empty( $metadata['name'] ) && str_starts_with( $metadata['name'], 'core/' ) ) {
+		$block_name = str_replace( 'core/', '', $metadata['name'] );
+
+		if ( ! isset( $metadata['style'] ) ) {
+			$metadata['style'] = "wp-block-$block_name";
+		}
+		if ( current_theme_supports( 'wp-block-styles' ) && wp_should_load_separate_core_block_assets() ) {
+			$metadata['style']   = (array) $metadata['style'];
+			$metadata['style'][] = "wp-block-{$block_name}-theme";
+		}
+		if ( ! isset( $metadata['editorStyle'] ) ) {
+			$metadata['editorStyle'] = "wp-block-{$block_name}-editor";
+		}
+	}
+
+	$settings          = array();
+	$property_mappings = array(
+		'apiVersion'      => 'api_version',
+		'title'           => 'title',
+		'category'        => 'category',
+		'parent'          => 'parent',
+		'ancestor'        => 'ancestor',
+		'icon'            => 'icon',
+		'description'     => 'description',
+		'keywords'        => 'keywords',
+		'attributes'      => 'attributes',
+		'providesContext' => 'provides_context',
+		'usesContext'     => 'uses_context',
+		'selectors'       => 'selectors',
+		'supports'        => 'supports',
+		'styles'          => 'styles',
+		'variations'      => 'variations',
+		'example'         => 'example',
+	);
+	$textdomain        = ! empty( $metadata['textdomain'] ) ? $metadata['textdomain'] : null;
+	$i18n_schema       = get_block_metadata_i18n_schema();
+
+	foreach ( $property_mappings as $key => $mapped_key ) {
+		if ( isset( $metadata[ $key ] ) ) {
+			$settings[ $mapped_key ] = $metadata[ $key ];
+			if ( $textdomain && isset( $i18n_schema->$key ) ) {
+				$settings[ $mapped_key ] = translate_settings_using_i18n_schema( $i18n_schema->$key, $settings[ $key ], $textdomain );
+			}
+		}
+	}
+
+	$script_fields = array(
+		'editorScript' => 'editor_script_handles',
+		'script'       => 'script_handles',
+		'viewScript'   => 'view_script_handles',
+	);
+	foreach ( $script_fields as $metadata_field_name => $settings_field_name ) {
+		if ( ! empty( $metadata[ $metadata_field_name ] ) ) {
+			$scripts           = $metadata[ $metadata_field_name ];
+			$processed_scripts = array();
+			if ( is_array( $scripts ) ) {
+				for ( $index = 0; $index < count( $scripts ); $index++ ) {
+					$result = register_block_script_handle(
+						$metadata,
+						$metadata_field_name,
+						$index
+					);
+					if ( $result ) {
+						$processed_scripts[] = $result;
+					}
+				}
+			} else {
+				$result = register_block_script_handle(
+					$metadata,
+					$metadata_field_name
+				);
+				if ( $result ) {
+					$processed_scripts[] = $result;
+				}
+			}
+			$settings[ $settings_field_name ] = $processed_scripts;
+		}
+	}
+
+	$style_fields = array(
+		'editorStyle' => 'editor_style_handles',
+		'style'       => 'style_handles',
+	);
+	foreach ( $style_fields as $metadata_field_name => $settings_field_name ) {
+		if ( ! empty( $metadata[ $metadata_field_name ] ) ) {
+			$styles           = $metadata[ $metadata_field_name ];
+			$processed_styles = array();
+			if ( is_array( $styles ) ) {
+				for ( $index = 0; $index < count( $styles ); $index++ ) {
+					$result = register_block_style_handle(
+						$metadata,
+						$metadata_field_name,
+						$index
+					);
+					if ( $result ) {
+						$processed_styles[] = $result;
+					}
+				}
+			} else {
+				$result = register_block_style_handle(
+					$metadata,
+					$metadata_field_name
+				);
+				if ( $result ) {
+					$processed_styles[] = $result;
+				}
+			}
+			$settings[ $settings_field_name ] = $processed_styles;
+		}
+	}
+
+	if ( ! empty( $metadata['blockHooks'] ) ) {
+		/**
+		 * Map camelCased position string (from block.json) to snake_cased block type position.
+		 *
+		 * @var array
+		 */
+		$position_mappings = array(
+			'before'     => 'before',
+			'after'      => 'after',
+			'firstChild' => 'first_child',
+			'lastChild'  => 'last_child',
+		);
+
+		$settings['block_hooks'] = array();
+		foreach ( $metadata['blockHooks'] as $anchor_block_name => $position ) {
+			// Avoid infinite recursion (hooking to itself).
+			if ( $metadata['name'] === $anchor_block_name ) {
+				_doing_it_wrong(
+					__METHOD__,
+					__( 'Cannot hook block to itself.' ),
+					'6.4.0'
+				);
+				continue;
+			}
+
+			if ( ! isset( $position_mappings[ $position ] ) ) {
+				continue;
+			}
+
+			$settings['block_hooks'][ $anchor_block_name ] = $position_mappings[ $position ];
+		}
+	}
+
+	if ( ! empty( $metadata['render'] ) ) {
+		$template_path = wp_normalize_path(
+			realpath(
+				dirname( $metadata['file'] ) . '/' .
+				remove_block_asset_path_prefix( $metadata['render'] )
+			)
+		);
+		if ( $template_path ) {
+			/**
+			 * Renders the block on the server.
+			 *
+			 * @since 6.1.0
+			 *
+			 * @param array    $attributes Block attributes.
+			 * @param string   $content    Block default content.
+			 * @param WP_Block $block      Block instance.
+			 *
+			 * @return string Returns the block content.
+			 */
+			$settings['render_callback'] = static function ( $attributes, $content, $block ) use ( $template_path ) {
+				ob_start();
+				require $template_path;
+				return ob_get_clean();
+			};
+		}
+	}
+
+	/**
+	 * Filters the settings determined from the block type metadata.
+	 *
+	 * @since 5.7.0
+	 *
+	 * @param array $settings Array of determined settings for registering a block type.
+	 * @param array $metadata Metadata provided for registering a block type.
+	 */
+	$settings = apply_filters(
+		'block_type_metadata_settings',
+		array_merge(
+			$settings,
+			$args
+		),
+		$metadata
+	);
+
+	return WP_Block_Type_Registry::get_instance()->register(
+		$metadata['name'],
+		$settings
+	);
+}
+
+/**
+ * Registers a block type. The recommended way is to register a block type using
+ * the metadata stored in the `block.json` file.
+ *
+ * @since 5.0.0
+ * @since 5.8.0 First parameter now accepts a path to the `block.json` file.
+ *
+ * @param string|WP_Block_Type $block_type Block type name including namespace, or alternatively
+ *                                         a path to the JSON file with metadata definition for the block,
+ *                                         or a path to the folder where the `block.json` file is located,
+ *                                         or a complete WP_Block_Type instance.
+ *                                         In case a WP_Block_Type is provided, the $args parameter will be ignored.
+ * @param array                $args       Optional. Array of block type arguments. Accepts any public property
+ *                                         of `WP_Block_Type`. See WP_Block_Type::__construct() for information
+ *                                         on accepted arguments. Default empty array.
+ *
+ * @return WP_Block_Type|false The registered block type on success, or false on failure.
+ */
+function register_block_type( $block_type, $args = array() ) {
+	if ( is_string( $block_type ) && file_exists( $block_type ) ) {
+		return register_block_type_from_metadata( $block_type, $args );
+	}
+
+	return WP_Block_Type_Registry::get_instance()->register( $block_type, $args );
+}
+
+/**
+ * Unregisters a block type.
+ *
+ * @since 5.0.0
+ *
+ * @param string|WP_Block_Type $name Block type name including namespace, or alternatively
+ *                                   a complete WP_Block_Type instance.
+ * @return WP_Block_Type|false The unregistered block type on success, or false on failure.
+ */
+function unregister_block_type( $name ) {
+	return WP_Block_Type_Registry::get_instance()->unregister( $name );
+}
+
+/**
+ * Determines whether a post or content string has blocks.
+ *
+ * This test optimizes for performance rather than strict accuracy, detecting
+ * the pattern of a block but not validating its structure. For strict accuracy,
+ * you should use the block parser on post content.
+ *
+ * @since 5.0.0
+ *
+ * @see parse_blocks()
+ *
+ * @param int|string|WP_Post|null $post Optional. Post content, post ID, or post object.
+ *                                      Defaults to global $post.
+ * @return bool Whether the post has blocks.
+ */
+function has_blocks( $post = null ) {
+	if ( ! is_string( $post ) ) {
+		$wp_post = get_post( $post );
+
+		if ( ! $wp_post instanceof WP_Post ) {
+			return false;
+		}
+
+		$post = $wp_post->post_content;
+	}
+
+	return str_contains( (string) $post, '<!-- wp:' );
+}
+
+/**
+ * Determines whether a $post or a string contains a specific block type.
+ *
+ * This test optimizes for performance rather than strict accuracy, detecting
+ * whether the block type exists but not validating its structure and not checking
+ * synced patterns (formerly called reusable blocks). For strict accuracy,
+ * you should use the block parser on post content.
+ *
+ * @since 5.0.0
+ *
+ * @see parse_blocks()
+ *
+ * @param string                  $block_name Full block type to look for.
+ * @param int|string|WP_Post|null $post       Optional. Post content, post ID, or post object.
+ *                                            Defaults to global $post.
+ * @return bool Whether the post content contains the specified block.
+ */
+function has_block( $block_name, $post = null ) {
+	if ( ! has_blocks( $post ) ) {
+		return false;
+	}
+
+	if ( ! is_string( $post ) ) {
+		$wp_post = get_post( $post );
+		if ( $wp_post instanceof WP_Post ) {
+			$post = $wp_post->post_content;
+		}
+	}
+
+	/*
+	 * Normalize block name to include namespace, if provided as non-namespaced.
+	 * This matches behavior for WordPress 5.0.0 - 5.3.0 in matching blocks by
+	 * their serialized names.
+	 */
+	if ( ! str_contains( $block_name, '/' ) ) {
+		$block_name = 'core/' . $block_name;
+	}
+
+	// Test for existence of block by its fully qualified name.
+	$has_block = str_contains( $post, '<!-- wp:' . $block_name . ' ' );
+
+	if ( ! $has_block ) {
+		/*
+		 * If the given block name would serialize to a different name, test for
+		 * existence by the serialized form.
+		 */
+		$serialized_block_name = strip_core_block_namespace( $block_name );
+		if ( $serialized_block_name !== $block_name ) {
+			$has_block = str_contains( $post, '<!-- wp:' . $serialized_block_name . ' ' );
+		}
+	}
+
+	return $has_block;
+}
+
+/**
+ * Returns an array of the names of all registered dynamic block types.
+ *
+ * @since 5.0.0
+ *
+ * @return string[] Array of dynamic block names.
+ */
+function get_dynamic_block_names() {
+	$dynamic_block_names = array();
+
+	$block_types = WP_Block_Type_Registry::get_instance()->get_all_registered();
+	foreach ( $block_types as $block_type ) {
+		if ( $block_type->is_dynamic() ) {
+			$dynamic_block_names[] = $block_type->name;
+		}
+	}
+
+	return $dynamic_block_names;
+}
+
+/**
+ * Retrieves block types hooked into the given block, grouped by anchor block type and the relative position.
+ *
+ * @since 6.4.0
+ *
+ * @return array[] Array of block types grouped by anchor block type and the relative position.
+ */
+function get_hooked_blocks() {
+	$block_types   = WP_Block_Type_Registry::get_instance()->get_all_registered();
+	$hooked_blocks = array();
+	foreach ( $block_types as $block_type ) {
+		if ( ! ( $block_type instanceof WP_Block_Type ) || ! is_array( $block_type->block_hooks ) ) {
+			continue;
+		}
+		foreach ( $block_type->block_hooks as $anchor_block_type => $relative_position ) {
+			if ( ! isset( $hooked_blocks[ $anchor_block_type ] ) ) {
+				$hooked_blocks[ $anchor_block_type ] = array();
+			}
+			if ( ! isset( $hooked_blocks[ $anchor_block_type ][ $relative_position ] ) ) {
+				$hooked_blocks[ $anchor_block_type ][ $relative_position ] = array();
+			}
+			$hooked_blocks[ $anchor_block_type ][ $relative_position ][] = $block_type->name;
+		}
+	}
+
+	return $hooked_blocks;
+}
+
+/**
+ * Returns a function that injects the theme attribute into, and hooked blocks before, a given block.
+ *
+ * The returned function can be used as `$pre_callback` argument to `traverse_and_serialize_block(s)`,
+ * where it will inject the `theme` attribute into all Template Part blocks, and prepend the markup for
+ * any blocks hooked `before` the given block and as its parent's `first_child`, respectively.
+ *
+ * This function is meant for internal use only.
+ *
+ * @since 6.4.0
+ * @access private
+ *
+ * @param array                   $hooked_blocks An array of blocks hooked to another given block.
+ * @param WP_Block_Template|array $context       A block template, template part, or pattern that the blocks belong to.
+ * @return callable A function that returns the serialized markup for the given block,
+ *                  including the markup for any hooked blocks before it.
+ */
+function make_before_block_visitor( $hooked_blocks, $context ) {
+	/**
+	 * Injects hooked blocks before the given block, injects the `theme` attribute into Template Part blocks, and returns the serialized markup.
+	 *
+	 * If the current block is a Template Part block, inject the `theme` attribute.
+	 * Furthermore, prepend the markup for any blocks hooked `before` the given block and as its parent's
+	 * `first_child`, respectively, to the serialized markup for the given block.
+	 *
+	 * @param array $block        The block to inject the theme attribute into, and hooked blocks before. Passed by reference.
+	 * @param array $parent_block The parent block of the given block. Passed by reference. Default null.
+	 * @param array $prev         The previous sibling block of the given block. Default null.
+	 * @return string The serialized markup for the given block, with the markup for any hooked blocks prepended to it.
+	 */
+	return function ( &$block, &$parent_block = null, $prev = null ) use ( $hooked_blocks, $context ) {
+		_inject_theme_attribute_in_template_part_block( $block );
+
+		$markup = '';
+
+		if ( $parent_block && ! $prev ) {
+			// Candidate for first-child insertion.
+			$relative_position  = 'first_child';
+			$anchor_block_type  = $parent_block['blockName'];
+			$hooked_block_types = isset( $hooked_blocks[ $anchor_block_type ][ $relative_position ] )
+				? $hooked_blocks[ $anchor_block_type ][ $relative_position ]
+				: array();
+
+			/**
+			 * Filters the list of hooked block types for a given anchor block type and relative position.
+			 *
+			 * @since 6.4.0
+			 *
+			 * @param string[]                $hooked_block_types  The list of hooked block types.
+			 * @param string                  $relative_position   The relative position of the hooked blocks.
+			 *                                                     Can be one of 'before', 'after', 'first_child', or 'last_child'.
+			 * @param string                  $anchor_block_type   The anchor block type.
+			 * @param WP_Block_Template|array $context             The block template, template part, or pattern that the anchor block belongs to.
+			 */
+			$hooked_block_types = apply_filters( 'hooked_block_types', $hooked_block_types, $relative_position, $anchor_block_type, $context );
+			foreach ( $hooked_block_types as $hooked_block_type ) {
+				$markup .= get_comment_delimited_block_content( $hooked_block_type, array(), '' );
+			}
+		}
+
+		$relative_position  = 'before';
+		$anchor_block_type  = $block['blockName'];
+		$hooked_block_types = isset( $hooked_blocks[ $anchor_block_type ][ $relative_position ] )
+			? $hooked_blocks[ $anchor_block_type ][ $relative_position ]
+			: array();
+
+		/** This filter is documented in wp-includes/blocks.php */
+		$hooked_block_types = apply_filters( 'hooked_block_types', $hooked_block_types, $relative_position, $anchor_block_type, $context );
+		foreach ( $hooked_block_types as $hooked_block_type ) {
+			$markup .= get_comment_delimited_block_content( $hooked_block_type, array(), '' );
+		}
+
+		return $markup;
+	};
+}
+
+/**
+ * Returns a function that injects the hooked blocks after a given block.
+ *
+ * The returned function can be used as `$post_callback` argument to `traverse_and_serialize_block(s)`,
+ * where it will append the markup for any blocks hooked `after` the given block and as its parent's
+ * `last_child`, respectively.
+ *
+ * This function is meant for internal use only.
+ *
+ * @since 6.4.0
+ * @access private
+ *
+ * @param array                   $hooked_blocks An array of blocks hooked to another block.
+ * @param WP_Block_Template|array $context       A block template, template part, or pattern that the blocks belong to.
+ * @return callable A function that returns the serialized markup for the given block,
+ *                  including the markup for any hooked blocks after it.
+ */
+function make_after_block_visitor( $hooked_blocks, $context ) {
+	/**
+	 * Injects hooked blocks after the given block, and returns the serialized markup.
+	 *
+	 * Append the markup for any blocks hooked `after` the given block and as its parent's
+	 * `last_child`, respectively, to the serialized markup for the given block.
+	 *
+	 * @param array $block        The block to inject the hooked blocks after. Passed by reference.
+	 * @param array $parent_block The parent block of the given block. Passed by reference. Default null.
+	 * @param array $next         The next sibling block of the given block. Default null.
+	 * @return string The serialized markup for the given block, with the markup for any hooked blocks appended to it.
+	 */
+	return function ( &$block, &$parent_block = null, $next = null ) use ( $hooked_blocks, $context ) {
+		$markup = '';
+
+		$relative_position  = 'after';
+		$anchor_block_type  = $block['blockName'];
+		$hooked_block_types = isset( $hooked_blocks[ $anchor_block_type ][ $relative_position ] )
+				? $hooked_blocks[ $anchor_block_type ][ $relative_position ]
+				: array();
+
+		/** This filter is documented in wp-includes/blocks.php */
+		$hooked_block_types = apply_filters( 'hooked_block_types', $hooked_block_types, $relative_position, $anchor_block_type, $context );
+		foreach ( $hooked_block_types as $hooked_block_type ) {
+			$markup .= get_comment_delimited_block_content( $hooked_block_type, array(), '' );
+		}
+
+		if ( $parent_block && ! $next ) {
+			// Candidate for last-child insertion.
+			$relative_position  = 'last_child';
+			$anchor_block_type  = $parent_block['blockName'];
+			$hooked_block_types = isset( $hooked_blocks[ $anchor_block_type ][ $relative_position ] )
+				? $hooked_blocks[ $anchor_block_type ][ $relative_position ]
+				: array();
+
+			/** This filter is documented in wp-includes/blocks.php */
+			$hooked_block_types = apply_filters( 'hooked_block_types', $hooked_block_types, $relative_position, $anchor_block_type, $context );
+			foreach ( $hooked_block_types as $hooked_block_type ) {
+				$markup .= get_comment_delimited_block_content( $hooked_block_type, array(), '' );
+			}
+		}
+
+		return $markup;
+	};
+}
+
+/**
+ * Given an array of attributes, returns a string in the serialized attributes
+ * format prepared for post content.
+ *
+ * The serialized result is a JSON-encoded string, with unicode escape sequence
+ * substitution for characters which might otherwise interfere with embedding
+ * the result in an HTML comment.
+ *
+ * This function must produce output that remains in sync with the output of
+ * the serializeAttributes JavaScript function in the block editor in order
+ * to ensure consistent operation between PHP and JavaScript.
+ *
+ * @since 5.3.1
+ *
+ * @param array $block_attributes Attributes object.
+ * @return string Serialized attributes.
+ */
+function serialize_block_attributes( $block_attributes ) {
+	$encoded_attributes = wp_json_encode( $block_attributes, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE );
+	$encoded_attributes = preg_replace( '/--/', '\\u002d\\u002d', $encoded_attributes );
+	$encoded_attributes = preg_replace( '/</', '\\u003c', $encoded_attributes );
+	$encoded_attributes = preg_replace( '/>/', '\\u003e', $encoded_attributes );
+	$encoded_attributes = preg_replace( '/&/', '\\u0026', $encoded_attributes );
+	// Regex: /\\"/
+	$encoded_attributes = preg_replace( '/\\\\"/', '\\u0022', $encoded_attributes );
+
+	return $encoded_attributes;
+}
+
+/**
+ * Returns the block name to use for serialization. This will remove the default
+ * "core/" namespace from a block name.
+ *
+ * @since 5.3.1
+ *
+ * @param string|null $block_name Optional. Original block name. Null if the block name is unknown,
+ *                                e.g. Classic blocks have their name set to null. Default null.
+ * @return string Block name to use for serialization.
+ */
+function strip_core_block_namespace( $block_name = null ) {
+	if ( is_string( $block_name ) && str_starts_with( $block_name, 'core/' ) ) {
+		return substr( $block_name, 5 );
+	}
+
+	return $block_name;
+}
+
+/**
+ * Returns the content of a block, including comment delimiters.
+ *
+ * @since 5.3.1
+ *
+ * @param string|null $block_name       Block name. Null if the block name is unknown,
+ *                                      e.g. Classic blocks have their name set to null.
+ * @param array       $block_attributes Block attributes.
+ * @param string      $block_content    Block save content.
+ * @return string Comment-delimited block content.
+ */
+function get_comment_delimited_block_content( $block_name, $block_attributes, $block_content ) {
+	if ( is_null( $block_name ) ) {
+		return $block_content;
+	}
+
+	$serialized_block_name = strip_core_block_namespace( $block_name );
+	$serialized_attributes = empty( $block_attributes ) ? '' : serialize_block_attributes( $block_attributes ) . ' ';
+
+	if ( empty( $block_content ) ) {
+		return sprintf( '<!-- wp:%s %s/-->', $serialized_block_name, $serialized_attributes );
+	}
+
+	return sprintf(
+		'<!-- wp:%s %s-->%s<!-- /wp:%s -->',
+		$serialized_block_name,
+		$serialized_attributes,
+		$block_content,
+		$serialized_block_name
+	);
+}
+
+/**
+ * Returns the content of a block, including comment delimiters, serializing all
+ * attributes from the given parsed block.
+ *
+ * This should be used when preparing a block to be saved to post content.
+ * Prefer `render_block` when preparing a block for display. Unlike
+ * `render_block`, this does not evaluate a block's `render_callback`, and will
+ * instead preserve the markup as parsed.
+ *
+ * @since 5.3.1
+ *
+ * @param array $block A representative array of a single parsed block object. See WP_Block_Parser_Block.
+ * @return string String of rendered HTML.
+ */
+function serialize_block( $block ) {
+	$block_content = '';
+
+	$index = 0;
+	foreach ( $block['innerContent'] as $chunk ) {
+		$block_content .= is_string( $chunk ) ? $chunk : serialize_block( $block['innerBlocks'][ $index++ ] );
+	}
+
+	if ( ! is_array( $block['attrs'] ) ) {
+		$block['attrs'] = array();
+	}
+
+	return get_comment_delimited_block_content(
+		$block['blockName'],
+		$block['attrs'],
+		$block_content
+	);
+}
+
+/**
+ * Returns a joined string of the aggregate serialization of the given
+ * parsed blocks.
+ *
+ * @since 5.3.1
+ *
+ * @param array[] $blocks An array of representative arrays of parsed block objects. See serialize_block().
+ * @return string String of rendered HTML.
+ */
+function serialize_blocks( $blocks ) {
+	return implode( '', array_map( 'serialize_block', $blocks ) );
+}
+
+/**
+ * Traverses a parsed block tree and applies callbacks before and after serializing it.
+ *
+ * Recursively traverses the block and its inner blocks and applies the two callbacks provided as
+ * arguments, the first one before serializing the block, and the second one after serializing it.
+ * If either callback returns a string value, it will be prepended and appended to the serialized
+ * block markup, respectively.
+ *
+ * The callbacks will receive a reference to the current block as their first argument, so that they
+ * can also modify it, and the current block's parent block as second argument. Finally, the
+ * `$pre_callback` receives the previous block, whereas the `$post_callback` receives
+ * the next block as third argument.
+ *
+ * Serialized blocks are returned including comment delimiters, and with all attributes serialized.
+ *
+ * This function should be used when there is a need to modify the saved block, or to inject markup
+ * into the return value. Prefer `serialize_block` when preparing a block to be saved to post content.
+ *
+ * This function is meant for internal use only.
+ *
+ * @since 6.4.0
+ * @access private
+ *
+ * @see serialize_block()
+ *
+ * @param array    $block         A representative array of a single parsed block object. See WP_Block_Parser_Block.
+ * @param callable $pre_callback  Callback to run on each block in the tree before it is traversed and serialized.
+ *                                It is called with the following arguments: &$block, $parent_block, $previous_block.
+ *                                Its string return value will be prepended to the serialized block markup.
+ * @param callable $post_callback Callback to run on each block in the tree after it is traversed and serialized.
+ *                                It is called with the following arguments: &$block, $parent_block, $next_block.
+ *                                Its string return value will be appended to the serialized block markup.
+ * @return string Serialized block markup.
+ */
+function traverse_and_serialize_block( $block, $pre_callback = null, $post_callback = null ) {
+	$block_content = '';
+	$block_index   = 0;
+
+	foreach ( $block['innerContent'] as $chunk ) {
+		if ( is_string( $chunk ) ) {
+			$block_content .= $chunk;
+		} else {
+			$inner_block = $block['innerBlocks'][ $block_index ];
+
+			if ( is_callable( $pre_callback ) ) {
+				$prev = 0 === $block_index
+					? null
+					: $block['innerBlocks'][ $block_index - 1 ];
+
+				$block_content .= call_user_func_array(
+					$pre_callback,
+					array( &$inner_block, &$block, $prev )
+				);
+			}
+
+			if ( is_callable( $post_callback ) ) {
+				$next = count( $block['innerBlocks'] ) - 1 === $block_index
+					? null
+					: $block['innerBlocks'][ $block_index + 1 ];
+
+				$post_markup = call_user_func_array(
+					$post_callback,
+					array( &$inner_block, &$block, $next )
+				);
+			}
+
+			$block_content .= traverse_and_serialize_block( $inner_block, $pre_callback, $post_callback );
+			$block_content .= isset( $post_markup ) ? $post_markup : '';
+
+			++$block_index;
+		}
+	}
+
+	if ( ! is_array( $block['attrs'] ) ) {
+		$block['attrs'] = array();
+	}
+
+	return get_comment_delimited_block_content(
+		$block['blockName'],
+		$block['attrs'],
+		$block_content
+	);
+}
+
+/**
+ * Given an array of parsed block trees, applies callbacks before and after serializing them and
+ * returns their concatenated output.
+ *
+ * Recursively traverses the blocks and their inner blocks and applies the two callbacks provided as
+ * arguments, the first one before serializing a block, and the second one after serializing.
+ * If either callback returns a string value, it will be prepended and appended to the serialized
+ * block markup, respectively.
+ *
+ * The callbacks will receive a reference to the current block as their first argument, so that they
+ * can also modify it, and the current block's parent block as second argument. Finally, the
+ * `$pre_callback` receives the previous block, whereas the `$post_callback` receives
+ * the next block as third argument.
+ *
+ * Serialized blocks are returned including comment delimiters, and with all attributes serialized.
+ *
+ * This function should be used when there is a need to modify the saved blocks, or to inject markup
+ * into the return value. Prefer `serialize_blocks` when preparing blocks to be saved to post content.
+ *
+ * This function is meant for internal use only.
+ *
+ * @since 6.4.0
+ * @access private
+ *
+ * @see serialize_blocks()
+ *
+ * @param array[]  $blocks        An array of parsed blocks. See WP_Block_Parser_Block.
+ * @param callable $pre_callback  Callback to run on each block in the tree before it is traversed and serialized.
+ *                                It is called with the following arguments: &$block, $parent_block, $previous_block.
+ *                                Its string return value will be prepended to the serialized block markup.
+ * @param callable $post_callback Callback to run on each block in the tree after it is traversed and serialized.
+ *                                It is called with the following arguments: &$block, $parent_block, $next_block.
+ *                                Its string return value will be appended to the serialized block markup.
+ * @return string Serialized block markup.
+ */
+function traverse_and_serialize_blocks( $blocks, $pre_callback = null, $post_callback = null ) {
+	$result       = '';
+	$parent_block = null; // At the top level, there is no parent block to pass to the callbacks; yet the callbacks expect a reference.
+
+	foreach ( $blocks as $index => $block ) {
+		if ( is_callable( $pre_callback ) ) {
+			$prev = 0 === $index
+				? null
+				: $blocks[ $index - 1 ];
+
+			$result .= call_user_func_array(
+				$pre_callback,
+				array( &$block, &$parent_block, $prev )
+			);
+		}
+
+		if ( is_callable( $post_callback ) ) {
+			$next = count( $blocks ) - 1 === $index
+				? null
+				: $blocks[ $index + 1 ];
+
+			$post_markup = call_user_func_array(
+				$post_callback,
+				array( &$block, &$parent_block, $next )
+			);
+		}
+
+		$result .= traverse_and_serialize_block( $block, $pre_callback, $post_callback );
+		$result .= isset( $post_markup ) ? $post_markup : '';
+	}
+
+	return $result;
+}
+
+/**
+ * Filters and sanitizes block content to remove non-allowable HTML
+ * from parsed block attribute values.
+ *
+ * @since 5.3.1
+ *
+ * @param string         $text              Text that may contain block content.
+ * @param array[]|string $allowed_html      Optional. An array of allowed HTML elements and attributes,
+ *                                          or a context name such as 'post'. See wp_kses_allowed_html()
+ *                                          for the list of accepted context names. Default 'post'.
+ * @param string[]       $allowed_protocols Optional. Array of allowed URL protocols.
+ *                                          Defaults to the result of wp_allowed_protocols().
+ * @return string The filtered and sanitized content result.
+ */
+function filter_block_content( $text, $allowed_html = 'post', $allowed_protocols = array() ) {
+	$result = '';
+
+	if ( str_contains( $text, '<!--' ) && str_contains( $text, '--->' ) ) {
+		$text = preg_replace_callback( '%<!--(.*?)--->%', '_filter_block_content_callback', $text );
+	}
+
+	$blocks = parse_blocks( $text );
+	foreach ( $blocks as $block ) {
+		$block   = filter_block_kses( $block, $allowed_html, $allowed_protocols );
+		$result .= serialize_block( $block );
+	}
+
+	return $result;
+}
+
+/**
+ * Callback used for regular expression replacement in filter_block_content().
+ *
+ * @private
+ * @since 6.2.1
+ *
+ * @param array $matches Array of preg_replace_callback matches.
+ * @return string Replacement string.
+ */
+function _filter_block_content_callback( $matches ) {
+	return '<!--' . rtrim( $matches[1], '-' ) . '-->';
+}
+
+/**
+ * Filters and sanitizes a parsed block to remove non-allowable HTML
+ * from block attribute values.
+ *
+ * @since 5.3.1
+ *
+ * @param WP_Block_Parser_Block $block             The parsed block object.
+ * @param array[]|string        $allowed_html      An array of allowed HTML elements and attributes,
+ *                                                 or a context name such as 'post'. See wp_kses_allowed_html()
+ *                                                 for the list of accepted context names.
+ * @param string[]              $allowed_protocols Optional. Array of allowed URL protocols.
+ *                                                 Defaults to the result of wp_allowed_protocols().
+ * @return array The filtered and sanitized block object result.
+ */
+function filter_block_kses( $block, $allowed_html, $allowed_protocols = array() ) {
+	$block['attrs'] = filter_block_kses_value( $block['attrs'], $allowed_html, $allowed_protocols );
+
+	if ( is_array( $block['innerBlocks'] ) ) {
+		foreach ( $block['innerBlocks'] as $i => $inner_block ) {
+			$block['innerBlocks'][ $i ] = filter_block_kses( $inner_block, $allowed_html, $allowed_protocols );
+		}
+	}
+
+	return $block;
+}
+
+/**
+ * Filters and sanitizes a parsed block attribute value to remove
+ * non-allowable HTML.
+ *
+ * @since 5.3.1
+ *
+ * @param string[]|string $value             The attribute value to filter.
+ * @param array[]|string  $allowed_html      An array of allowed HTML elements and attributes,
+ *                                           or a context name such as 'post'. See wp_kses_allowed_html()
+ *                                           for the list of accepted context names.
+ * @param string[]        $allowed_protocols Optional. Array of allowed URL protocols.
+ *                                           Defaults to the result of wp_allowed_protocols().
+ * @return string[]|string The filtered and sanitized result.
+ */
+function filter_block_kses_value( $value, $allowed_html, $allowed_protocols = array() ) {
+	if ( is_array( $value ) ) {
+		foreach ( $value as $key => $inner_value ) {
+			$filtered_key   = filter_block_kses_value( $key, $allowed_html, $allowed_protocols );
+			$filtered_value = filter_block_kses_value( $inner_value, $allowed_html, $allowed_protocols );
+
+			if ( $filtered_key !== $key ) {
+				unset( $value[ $key ] );
+			}
+
+			$value[ $filtered_key ] = $filtered_value;
+		}
+	} elseif ( is_string( $value ) ) {
+		return wp_kses( $value, $allowed_html, $allowed_protocols );
+	}
+
+	return $value;
+}
+
+/**
+ * Parses blocks out of a content string, and renders those appropriate for the excerpt.
+ *
+ * As the excerpt should be a small string of text relevant to the full post content,
+ * this function renders the blocks that are most likely to contain such text.
+ *
+ * @since 5.0.0
+ *
+ * @param string $content The content to parse.
+ * @return string The parsed and filtered content.
+ */
+function excerpt_remove_blocks( $content ) {
+	if ( ! has_blocks( $content ) ) {
+		return $content;
+	}
+
+	$allowed_inner_blocks = array(
+		// Classic blocks have their blockName set to null.
+		null,
+		'core/freeform',
+		'core/heading',
+		'core/html',
+		'core/list',
+		'core/media-text',
+		'core/paragraph',
+		'core/preformatted',
+		'core/pullquote',
+		'core/quote',
+		'core/table',
+		'core/verse',
+	);
+
+	$allowed_wrapper_blocks = array(
+		'core/columns',
+		'core/column',
+		'core/group',
+	);
+
+	/**
+	 * Filters the list of blocks that can be used as wrapper blocks, allowing
+	 * excerpts to be generated from the `innerBlocks` of these wrappers.
+	 *
+	 * @since 5.8.0
+	 *
+	 * @param string[] $allowed_wrapper_blocks The list of names of allowed wrapper blocks.
+	 */
+	$allowed_wrapper_blocks = apply_filters( 'excerpt_allowed_wrapper_blocks', $allowed_wrapper_blocks );
+
+	$allowed_blocks = array_merge( $allowed_inner_blocks, $allowed_wrapper_blocks );
+
+	/**
+	 * Filters the list of blocks that can contribute to the excerpt.
+	 *
+	 * If a dynamic block is added to this list, it must not generate another
+	 * excerpt, as this will cause an infinite loop to occur.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string[] $allowed_blocks The list of names of allowed blocks.
+	 */
+	$allowed_blocks = apply_filters( 'excerpt_allowed_blocks', $allowed_blocks );
+	$blocks         = parse_blocks( $content );
+	$output         = '';
+
+	foreach ( $blocks as $block ) {
+		if ( in_array( $block['blockName'], $allowed_blocks, true ) ) {
+			if ( ! empty( $block['innerBlocks'] ) ) {
+				if ( in_array( $block['blockName'], $allowed_wrapper_blocks, true ) ) {
+					$output .= _excerpt_render_inner_blocks( $block, $allowed_blocks );
+					continue;
+				}
+
+				// Skip the block if it has disallowed or nested inner blocks.
+				foreach ( $block['innerBlocks'] as $inner_block ) {
+					if (
+						! in_array( $inner_block['blockName'], $allowed_inner_blocks, true ) ||
+						! empty( $inner_block['innerBlocks'] )
+					) {
+						continue 2;
+					}
+				}
+			}
+
+			$output .= render_block( $block );
+		}
+	}
+
+	return $output;
+}
+
+/**
+ * Parses footnotes markup out of a content string,
+ * and renders those appropriate for the excerpt.
+ *
+ * @since 6.3.0
+ *
+ * @param string $content The content to parse.
+ * @return string The parsed and filtered content.
+ */
+function excerpt_remove_footnotes( $content ) {
+	if ( ! str_contains( $content, 'data-fn=' ) ) {
+		return $content;
+	}
+
+	return preg_replace(
+		'_<sup data-fn="[^"]+" class="[^"]+">\s*<a href="[^"]+" id="[^"]+">\d+</a>\s*</sup>_',
+		'',
+		$content
+	);
+}
+
+/**
+ * Renders inner blocks from the allowed wrapper blocks
+ * for generating an excerpt.
+ *
+ * @since 5.8.0
+ * @access private
+ *
+ * @param array $parsed_block   The parsed block.
+ * @param array $allowed_blocks The list of allowed inner blocks.
+ * @return string The rendered inner blocks.
+ */
+function _excerpt_render_inner_blocks( $parsed_block, $allowed_blocks ) {
+	$output = '';
+
+	foreach ( $parsed_block['innerBlocks'] as $inner_block ) {
+		if ( ! in_array( $inner_block['blockName'], $allowed_blocks, true ) ) {
+			continue;
+		}
+
+		if ( empty( $inner_block['innerBlocks'] ) ) {
+			$output .= render_block( $inner_block );
+		} else {
+			$output .= _excerpt_render_inner_blocks( $inner_block, $allowed_blocks );
+		}
+	}
+
+	return $output;
+}
+
+/**
+ * Renders a single block into a HTML string.
+ *
+ * @since 5.0.0
+ *
+ * @global WP_Post $post The post to edit.
+ *
+ * @param array $parsed_block A single parsed block object.
+ * @return string String of rendered HTML.
+ */
+function render_block( $parsed_block ) {
+	global $post;
+	$parent_block = null;
+
+	/**
+	 * Allows render_block() to be short-circuited, by returning a non-null value.
+	 *
+	 * @since 5.1.0
+	 * @since 5.9.0 The `$parent_block` parameter was added.
+	 *
+	 * @param string|null   $pre_render   The pre-rendered content. Default null.
+	 * @param array         $parsed_block The block being rendered.
+	 * @param WP_Block|null $parent_block If this is a nested block, a reference to the parent block.
+	 */
+	$pre_render = apply_filters( 'pre_render_block', null, $parsed_block, $parent_block );
+	if ( ! is_null( $pre_render ) ) {
+		return $pre_render;
+	}
+
+	$source_block = $parsed_block;
+
+	/**
+	 * Filters the block being rendered in render_block(), before it's processed.
+	 *
+	 * @since 5.1.0
+	 * @since 5.9.0 The `$parent_block` parameter was added.
+	 *
+	 * @param array         $parsed_block The block being rendered.
+	 * @param array         $source_block An un-modified copy of $parsed_block, as it appeared in the source content.
+	 * @param WP_Block|null $parent_block If this is a nested block, a reference to the parent block.
+	 */
+	$parsed_block = apply_filters( 'render_block_data', $parsed_block, $source_block, $parent_block );
+
+	$context = array();
+
+	if ( $post instanceof WP_Post ) {
+		$context['postId'] = $post->ID;
+
+		/*
+		 * The `postType` context is largely unnecessary server-side, since the ID
+		 * is usually sufficient on its own. That being said, since a block's
+		 * manifest is expected to be shared between the server and the client,
+		 * it should be included to consistently fulfill the expectation.
+		 */
+		$context['postType'] = $post->post_type;
+	}
+
+	/**
+	 * Filters the default context provided to a rendered block.
+	 *
+	 * @since 5.5.0
+	 * @since 5.9.0 The `$parent_block` parameter was added.
+	 *
+	 * @param array         $context      Default context.
+	 * @param array         $parsed_block Block being rendered, filtered by `render_block_data`.
+	 * @param WP_Block|null $parent_block If this is a nested block, a reference to the parent block.
+	 */
+	$context = apply_filters( 'render_block_context', $context, $parsed_block, $parent_block );
+
+	$block = new WP_Block( $parsed_block, $context );
+
+	return $block->render();
+}
+
+/**
+ * Parses blocks out of a content string.
+ *
+ * @since 5.0.0
+ *
+ * @param string $content Post content.
+ * @return array[] Array of parsed block objects.
+ */
+function parse_blocks( $content ) {
+	/**
+	 * Filter to allow plugins to replace the server-side block parser.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string $parser_class Name of block parser class.
+	 */
+	$parser_class = apply_filters( 'block_parser_class', 'WP_Block_Parser' );
+
+	$parser = new $parser_class();
+	return $parser->parse( $content );
+}
+
+/**
+ * Parses dynamic blocks out of `post_content` and re-renders them.
+ *
+ * @since 5.0.0
+ *
+ * @param string $content Post content.
+ * @return string Updated post content.
+ */
+function do_blocks( $content ) {
+	$blocks = parse_blocks( $content );
+	$output = '';
+
+	foreach ( $blocks as $block ) {
+		$output .= render_block( $block );
+	}
+
+	// If there are blocks in this content, we shouldn't run wpautop() on it later.
+	$priority = has_filter( 'the_content', 'wpautop' );
+	if ( false !== $priority && doing_filter( 'the_content' ) && has_blocks( $content ) ) {
+		remove_filter( 'the_content', 'wpautop', $priority );
+		add_filter( 'the_content', '_restore_wpautop_hook', $priority + 1 );
+	}
+
+	return $output;
+}
+
+/**
+ * If do_blocks() needs to remove wpautop() from the `the_content` filter, this re-adds it afterwards,
+ * for subsequent `the_content` usage.
+ *
+ * @since 5.0.0
+ * @access private
+ *
+ * @param string $content The post content running through this filter.
+ * @return string The unmodified content.
+ */
+function _restore_wpautop_hook( $content ) {
+	$current_priority = has_filter( 'the_content', '_restore_wpautop_hook' );
+
+	add_filter( 'the_content', 'wpautop', $current_priority - 1 );
+	remove_filter( 'the_content', '_restore_wpautop_hook', $current_priority );
+
+	return $content;
+}
+
+/**
+ * Returns the current version of the block format that the content string is using.
+ *
+ * If the string doesn't contain blocks, it returns 0.
+ *
+ * @since 5.0.0
+ *
+ * @param string $content Content to test.
+ * @return int The block format version is 1 if the content contains one or more blocks, 0 otherwise.
+ */
+function block_version( $content ) {
+	return has_blocks( $content ) ? 1 : 0;
+}
+
+/**
+ * Registers a new block style.
+ *
+ * @since 5.3.0
+ *
+ * @link https://developer.wordpress.org/block-editor/reference-guides/block-api/block-styles/
+ *
+ * @param string $block_name       Block type name including namespace.
+ * @param array  $style_properties Array containing the properties of the style name, label,
+ *                                 style_handle (name of the stylesheet to be enqueued),
+ *                                 inline_style (string containing the CSS to be added).
+ * @return bool True if the block style was registered with success and false otherwise.
+ */
+function register_block_style( $block_name, $style_properties ) {
+	return WP_Block_Styles_Registry::get_instance()->register( $block_name, $style_properties );
+}
+
+/**
+ * Unregisters a block style.
+ *
+ * @since 5.3.0
+ *
+ * @param string $block_name       Block type name including namespace.
+ * @param string $block_style_name Block style name.
+ * @return bool True if the block style was unregistered with success and false otherwise.
+ */
+function unregister_block_style( $block_name, $block_style_name ) {
+	return WP_Block_Styles_Registry::get_instance()->unregister( $block_name, $block_style_name );
+}
+
+/**
+ * Checks whether the current block type supports the feature requested.
+ *
+ * @since 5.8.0
+ * @since 6.4.0 The `$feature` parameter now supports a string.
+ *
+ * @param WP_Block_Type $block_type    Block type to check for support.
+ * @param string|array  $feature       Feature slug, or path to a specific feature to check support for.
+ * @param mixed         $default_value Optional. Fallback value for feature support. Default false.
+ * @return bool Whether the feature is supported.
+ */
+function block_has_support( $block_type, $feature, $default_value = false ) {
+	$block_support = $default_value;
+	if ( $block_type instanceof WP_Block_Type ) {
+		if ( is_array( $feature ) && count( $feature ) === 1 ) {
+			$feature = $feature[0];
+		}
+
+		if ( is_array( $feature ) ) {
+			$block_support = _wp_array_get( $block_type->supports, $feature, $default_value );
+		} elseif ( isset( $block_type->supports[ $feature ] ) ) {
+			$block_support = $block_type->supports[ $feature ];
+		}
+	}
+
+	return true === $block_support || is_array( $block_support );
+}
+
+/**
+ * Converts typography keys declared under `supports.*` to `supports.typography.*`.
+ *
+ * Displays a `_doing_it_wrong()` notice when a block using the older format is detected.
+ *
+ * @since 5.8.0
+ *
+ * @param array $metadata Metadata for registering a block type.
+ * @return array Filtered metadata for registering a block type.
+ */
+function wp_migrate_old_typography_shape( $metadata ) {
+	if ( ! isset( $metadata['supports'] ) ) {
+		return $metadata;
+	}
+
+	$typography_keys = array(
+		'__experimentalFontFamily',
+		'__experimentalFontStyle',
+		'__experimentalFontWeight',
+		'__experimentalLetterSpacing',
+		'__experimentalTextDecoration',
+		'__experimentalTextTransform',
+		'fontSize',
+		'lineHeight',
+	);
+
+	foreach ( $typography_keys as $typography_key ) {
+		$support_for_key = isset( $metadata['supports'][ $typography_key ] ) ? $metadata['supports'][ $typography_key ] : null;
+
+		if ( null !== $support_for_key ) {
+			_doing_it_wrong(
+				'register_block_type_from_metadata()',
+				sprintf(
+					/* translators: 1: Block type, 2: Typography supports key, e.g: fontSize, lineHeight, etc. 3: block.json, 4: Old metadata key, 5: New metadata key. */
+					__( 'Block "%1$s" is declaring %2$s support in %3$s file under %4$s. %2$s support is now declared under %5$s.' ),
+					$metadata['name'],
+					"<code>$typography_key</code>",
+					'<code>block.json</code>',
+					"<code>supports.$typography_key</code>",
+					"<code>supports.typography.$typography_key</code>"
+				),
+				'5.8.0'
+			);
+
+			_wp_array_set( $metadata['supports'], array( 'typography', $typography_key ), $support_for_key );
+			unset( $metadata['supports'][ $typography_key ] );
+		}
+	}
+
+	return $metadata;
+}
+
+/**
+ * Helper function that constructs a WP_Query args array from
+ * a `Query` block properties.
+ *
+ * It's used in Query Loop, Query Pagination Numbers and Query Pagination Next blocks.
+ *
+ * @since 5.8.0
+ * @since 6.1.0 Added `query_loop_block_query_vars` filter and `parents` support in query.
+ *
+ * @param WP_Block $block Block instance.
+ * @param int      $page  Current query's page.
+ *
+ * @return array Returns the constructed WP_Query arguments.
+ */
+function build_query_vars_from_query_block( $block, $page ) {
+	$query = array(
+		'post_type'    => 'post',
+		'order'        => 'DESC',
+		'orderby'      => 'date',
+		'post__not_in' => array(),
+	);
+
+	if ( isset( $block->context['query'] ) ) {
+		if ( ! empty( $block->context['query']['postType'] ) ) {
+			$post_type_param = $block->context['query']['postType'];
+			if ( is_post_type_viewable( $post_type_param ) ) {
+				$query['post_type'] = $post_type_param;
+			}
+		}
+		if ( isset( $block->context['query']['sticky'] ) && ! empty( $block->context['query']['sticky'] ) ) {
+			$sticky = get_option( 'sticky_posts' );
+			if ( 'only' === $block->context['query']['sticky'] ) {
+				/*
+				 * Passing an empty array to post__in will return have_posts() as true (and all posts will be returned).
+				 * Logic should be used before hand to determine if WP_Query should be used in the event that the array
+				 * being passed to post__in is empty.
+				 *
+				 * @see https://core.trac.wordpress.org/ticket/28099
+				 */
+				$query['post__in']            = ! empty( $sticky ) ? $sticky : array( 0 );
+				$query['ignore_sticky_posts'] = 1;
+			} else {
+				$query['post__not_in'] = array_merge( $query['post__not_in'], $sticky );
+			}
+		}
+		if ( ! empty( $block->context['query']['exclude'] ) ) {
+			$excluded_post_ids     = array_map( 'intval', $block->context['query']['exclude'] );
+			$excluded_post_ids     = array_filter( $excluded_post_ids );
+			$query['post__not_in'] = array_merge( $query['post__not_in'], $excluded_post_ids );
+		}
+		if (
+			isset( $block->context['query']['perPage'] ) &&
+			is_numeric( $block->context['query']['perPage'] )
+		) {
+			$per_page = absint( $block->context['query']['perPage'] );
+			$offset   = 0;
+
+			if (
+				isset( $block->context['query']['offset'] ) &&
+				is_numeric( $block->context['query']['offset'] )
+			) {
+				$offset = absint( $block->context['query']['offset'] );
+			}
+
+			$query['offset']         = ( $per_page * ( $page - 1 ) ) + $offset;
+			$query['posts_per_page'] = $per_page;
+		}
+		// Migrate `categoryIds` and `tagIds` to `tax_query` for backwards compatibility.
+		if ( ! empty( $block->context['query']['categoryIds'] ) || ! empty( $block->context['query']['tagIds'] ) ) {
+			$tax_query = array();
+			if ( ! empty( $block->context['query']['categoryIds'] ) ) {
+				$tax_query[] = array(
+					'taxonomy'         => 'category',
+					'terms'            => array_filter( array_map( 'intval', $block->context['query']['categoryIds'] ) ),
+					'include_children' => false,
+				);
+			}
+			if ( ! empty( $block->context['query']['tagIds'] ) ) {
+				$tax_query[] = array(
+					'taxonomy'         => 'post_tag',
+					'terms'            => array_filter( array_map( 'intval', $block->context['query']['tagIds'] ) ),
+					'include_children' => false,
+				);
+			}
+			$query['tax_query'] = $tax_query;
+		}
+		if ( ! empty( $block->context['query']['taxQuery'] ) ) {
+			$query['tax_query'] = array();
+			foreach ( $block->context['query']['taxQuery'] as $taxonomy => $terms ) {
+				if ( is_taxonomy_viewable( $taxonomy ) && ! empty( $terms ) ) {
+					$query['tax_query'][] = array(
+						'taxonomy'         => $taxonomy,
+						'terms'            => array_filter( array_map( 'intval', $terms ) ),
+						'include_children' => false,
+					);
+				}
+			}
+		}
+		if (
+			isset( $block->context['query']['order'] ) &&
+				in_array( strtoupper( $block->context['query']['order'] ), array( 'ASC', 'DESC' ), true )
+		) {
+			$query['order'] = strtoupper( $block->context['query']['order'] );
+		}
+		if ( isset( $block->context['query']['orderBy'] ) ) {
+			$query['orderby'] = $block->context['query']['orderBy'];
+		}
+		if (
+			isset( $block->context['query']['author'] )
+		) {
+			if ( is_array( $block->context['query']['author'] ) ) {
+				$query['author__in'] = array_filter( array_map( 'intval', $block->context['query']['author'] ) );
+			} elseif ( is_string( $block->context['query']['author'] ) ) {
+				$query['author__in'] = array_filter( array_map( 'intval', explode( ',', $block->context['query']['author'] ) ) );
+			} elseif ( is_int( $block->context['query']['author'] ) && $block->context['query']['author'] > 0 ) {
+				$query['author'] = $block->context['query']['author'];
+			}
+		}
+		if ( ! empty( $block->context['query']['search'] ) ) {
+			$query['s'] = $block->context['query']['search'];
+		}
+		if ( ! empty( $block->context['query']['parents'] ) && is_post_type_hierarchical( $query['post_type'] ) ) {
+			$query['post_parent__in'] = array_filter( array_map( 'intval', $block->context['query']['parents'] ) );
+		}
+	}
+
+	/**
+	 * Filters the arguments which will be passed to `WP_Query` for the Query Loop Block.
+	 *
+	 * Anything to this filter should be compatible with the `WP_Query` API to form
+	 * the query context which will be passed down to the Query Loop Block's children.
+	 * This can help, for example, to include additional settings or meta queries not
+	 * directly supported by the core Query Loop Block, and extend its capabilities.
+	 *
+	 * Please note that this will only influence the query that will be rendered on the
+	 * front-end. The editor preview is not affected by this filter. Also, worth noting
+	 * that the editor preview uses the REST API, so, ideally, one should aim to provide
+	 * attributes which are also compatible with the REST API, in order to be able to
+	 * implement identical queries on both sides.
+	 *
+	 * @since 6.1.0
+	 *
+	 * @param array    $query Array containing parameters for `WP_Query` as parsed by the block context.
+	 * @param WP_Block $block Block instance.
+	 * @param int      $page  Current query's page.
+	 */
+	return apply_filters( 'query_loop_block_query_vars', $query, $block, $page );
+}
+
+/**
+ * Helper function that returns the proper pagination arrow HTML for
+ * `QueryPaginationNext` and `QueryPaginationPrevious` blocks based
+ * on the provided `paginationArrow` from `QueryPagination` context.
+ *
+ * It's used in QueryPaginationNext and QueryPaginationPrevious blocks.
+ *
+ * @since 5.9.0
+ *
+ * @param WP_Block $block   Block instance.
+ * @param bool     $is_next Flag for handling `next/previous` blocks.
+ * @return string|null The pagination arrow HTML or null if there is none.
+ */
+function get_query_pagination_arrow( $block, $is_next ) {
+	$arrow_map = array(
+		'none'    => '',
+		'arrow'   => array(
+			'next'     => '→',
+			'previous' => '←',
+		),
+		'chevron' => array(
+			'next'     => '»',
+			'previous' => '«',
+		),
+	);
+	if ( ! empty( $block->context['paginationArrow'] ) && array_key_exists( $block->context['paginationArrow'], $arrow_map ) && ! empty( $arrow_map[ $block->context['paginationArrow'] ] ) ) {
+		$pagination_type = $is_next ? 'next' : 'previous';
+		$arrow_attribute = $block->context['paginationArrow'];
+		$arrow           = $arrow_map[ $block->context['paginationArrow'] ][ $pagination_type ];
+		$arrow_classes   = "wp-block-query-pagination-$pagination_type-arrow is-arrow-$arrow_attribute";
+		return "<span class='$arrow_classes' aria-hidden='true'>$arrow</span>";
+	}
+	return null;
+}
+
+/**
+ * Helper function that constructs a comment query vars array from the passed
+ * block properties.
+ *
+ * It's used with the Comment Query Loop inner blocks.
+ *
+ * @since 6.0.0
+ *
+ * @param WP_Block $block Block instance.
+ * @return array Returns the comment query parameters to use with the
+ *               WP_Comment_Query constructor.
+ */
+function build_comment_query_vars_from_block( $block ) {
+
+	$comment_args = array(
+		'orderby'       => 'comment_date_gmt',
+		'order'         => 'ASC',
+		'status'        => 'approve',
+		'no_found_rows' => false,
+	);
+
+	if ( is_user_logged_in() ) {
+		$comment_args['include_unapproved'] = array( get_current_user_id() );
+	} else {
+		$unapproved_email = wp_get_unapproved_comment_author_email();
+
+		if ( $unapproved_email ) {
+			$comment_args['include_unapproved'] = array( $unapproved_email );
+		}
+	}
+
+	if ( ! empty( $block->context['postId'] ) ) {
+		$comment_args['post_id'] = (int) $block->context['postId'];
+	}
+
+	if ( get_option( 'thread_comments' ) ) {
+		$comment_args['hierarchical'] = 'threaded';
+	} else {
+		$comment_args['hierarchical'] = false;
+	}
+
+	if ( get_option( 'page_comments' ) === '1' || get_option( 'page_comments' ) === true ) {
+		$per_page     = get_option( 'comments_per_page' );
+		$default_page = get_option( 'default_comments_page' );
+		if ( $per_page > 0 ) {
+			$comment_args['number'] = $per_page;
+
+			$page = (int) get_query_var( 'cpage' );
+			if ( $page ) {
+				$comment_args['paged'] = $page;
+			} elseif ( 'oldest' === $default_page ) {
+				$comment_args['paged'] = 1;
+			} elseif ( 'newest' === $default_page ) {
+				$max_num_pages = (int) ( new WP_Comment_Query( $comment_args ) )->max_num_pages;
+				if ( 0 !== $max_num_pages ) {
+					$comment_args['paged'] = $max_num_pages;
+				}
+			}
+			// Set the `cpage` query var to ensure the previous and next pagination links are correct
+			// when inheriting the Discussion Settings.
+			if ( 0 === $page && isset( $comment_args['paged'] ) && $comment_args['paged'] > 0 ) {
+				set_query_var( 'cpage', $comment_args['paged'] );
+			}
+		}
+	}
+
+	return $comment_args;
+}
+
+/**
+ * Helper function that returns the proper pagination arrow HTML for
+ * `CommentsPaginationNext` and `CommentsPaginationPrevious` blocks based on the
+ * provided `paginationArrow` from `CommentsPagination` context.
+ *
+ * It's used in CommentsPaginationNext and CommentsPaginationPrevious blocks.
+ *
+ * @since 6.0.0
+ *
+ * @param WP_Block $block           Block instance.
+ * @param string   $pagination_type Optional. Type of the arrow we will be rendering.
+ *                                  Accepts 'next' or 'previous'. Default 'next'.
+ * @return string|null The pagination arrow HTML or null if there is none.
+ */
+function get_comments_pagination_arrow( $block, $pagination_type = 'next' ) {
+	$arrow_map = array(
+		'none'    => '',
+		'arrow'   => array(
+			'next'     => '→',
+			'previous' => '←',
+		),
+		'chevron' => array(
+			'next'     => '»',
+			'previous' => '«',
+		),
+	);
+	if ( ! empty( $block->context['comments/paginationArrow'] ) && ! empty( $arrow_map[ $block->context['comments/paginationArrow'] ][ $pagination_type ] ) ) {
+		$arrow_attribute = $block->context['comments/paginationArrow'];
+		$arrow           = $arrow_map[ $block->context['comments/paginationArrow'] ][ $pagination_type ];
+		$arrow_classes   = "wp-block-comments-pagination-$pagination_type-arrow is-arrow-$arrow_attribute";
+		return "<span class='$arrow_classes' aria-hidden='true'>$arrow</span>";
+	}
+	return null;
+}
+
+/**
+ * Strips all HTML from the content of footnotes, and sanitizes the ID.
+ * This function expects slashed data on the footnotes content.
+ *
+ * @access private
+ * @since 6.3.2
+ *
+ * @param string $footnotes JSON encoded string of an array containing the content and ID of each footnote.
+ * @return string Filtered content without any HTML on the footnote content and with the sanitized id.
+ */
+function _wp_filter_post_meta_footnotes( $footnotes ) {
+	$footnotes_decoded   = json_decode( $footnotes, true );
+	if ( ! is_array( $footnotes_decoded ) ) {
+		return '';
+	}
+	$footnotes_sanitized = array();
+	foreach ( $footnotes_decoded as $footnote ) {
+		if ( ! empty( $footnote['content'] ) && ! empty( $footnote['id'] ) ) {
+			$footnotes_sanitized[] = array(
+				'id'      => sanitize_key( $footnote['id'] ),
+				'content' => wp_unslash( wp_filter_post_kses( wp_slash( $footnote['content'] ) ) ),
+			);
+		}
+	}
+	return wp_json_encode( $footnotes_sanitized );
+}
+
+/**
+ * Adds the filters to filter footnotes meta field.
+ *
+ * @access private
+ * @since 6.3.2
+ */
+function _wp_footnotes_kses_init_filters() {
+	add_filter( 'sanitize_post_meta_footnotes', '_wp_filter_post_meta_footnotes' );
+}
+
+/**
+ * Removes the filters that filter footnotes meta field.
+ *
+ * @access private
+ * @since 6.3.2
+ */
+function _wp_footnotes_remove_filters() {
+	remove_filter( 'sanitize_post_meta_footnotes', '_wp_filter_post_meta_footnotes' );
+}
+
+/**
+ * Registers the filter of footnotes meta field if the user does not have unfiltered_html capability.
+ *
+ * @access private
+ * @since 6.3.2
+ */
+function _wp_footnotes_kses_init() {
+	_wp_footnotes_remove_filters();
+	if ( ! current_user_can( 'unfiltered_html' ) ) {
+		_wp_footnotes_kses_init_filters();
+	}
+}
+
+/**
+ * Initializes footnotes meta field filters when imported data should be filtered.
+ *
+ * This filter is the last being executed on force_filtered_html_on_import.
+ * If the input of the filter is true it means we are in an import situation and should
+ * enable kses, independently of the user capabilities.
+ * So in that case we call _wp_footnotes_kses_init_filters;
+ *
+ * @access private
+ * @since 6.3.2
+ *
+ * @param string $arg Input argument of the filter.
+ * @return string Input argument of the filter.
+ */
+function _wp_footnotes_force_filtered_html_on_import_filter( $arg ) {
+	// force_filtered_html_on_import is true we need to init the global styles kses filters.
+	if ( $arg ) {
+		_wp_footnotes_kses_init_filters();
+	}
+	return $arg;
+}