diff --git a/src/wp-includes/block-bindings.php b/src/wp-includes/block-bindings.php
index 1250f92e99848..7809e05cd4185 100644
--- a/src/wp-includes/block-bindings.php
+++ b/src/wp-includes/block-bindings.php
@@ -138,6 +138,7 @@ function get_block_bindings_source( string $source_name ) {
  * @since 6.9.0
  * @since 7.1.0 Added support for the List Item block.
  * @since 7.2.0 Added support for the Icon block.
+ * @since 7.3.0 Added support for the inner blocks of the Group and Column blocks.
  *
  * @param string $block_type The block type whose supported attributes are being retrieved.
  * @return array The list of block attributes that are supported by block bindings.
@@ -153,6 +154,8 @@ function get_block_bindings_supported_attributes( $block_type ) {
 		'core/navigation-link'    => array( 'url' ),
 		'core/navigation-submenu' => array( 'url' ),
 		'core/icon'               => array( 'icon' ),
+		'core/group'              => array( 'innerBlocks' ),
+		'core/column'             => array( 'innerBlocks' ),
 	);
 
 	$supported_block_attributes =
diff --git a/src/wp-includes/block-editor.php b/src/wp-includes/block-editor.php
index 24bdd2f6db5db..caf4d7d38db59 100644
--- a/src/wp-includes/block-editor.php
+++ b/src/wp-includes/block-editor.php
@@ -485,6 +485,8 @@ function wp_get_post_content_block_attributes() {
  * Returns the contextualized block editor settings for a selected editor context.
  *
  * @since 5.8.0
+ * @since 7.3.0 Leaves `innerBlocks` out of the attributes that block bindings support,
+ *              as the editor doesn't render its bindings yet.
  *
  * @param array                   $custom_settings      Custom settings to use with the given editor type.
  * @param WP_Block_Editor_Context $block_editor_context The current block editor context.
@@ -502,7 +504,7 @@ function get_block_editor_settings( array $custom_settings, $block_editor_contex
 
 	$editor_settings['__experimentalBlockBindingsSupportedAttributes'] = array();
 	foreach ( array_keys( WP_Block_Type_Registry::get_instance()->get_all_registered() ) as $block_type ) {
-		$supported_block_attributes = get_block_bindings_supported_attributes( $block_type );
+		$supported_block_attributes = array_values( array_diff( get_block_bindings_supported_attributes( $block_type ), array( 'innerBlocks' ) ) );
 		if ( ! empty( $supported_block_attributes ) ) {
 			$editor_settings['__experimentalBlockBindingsSupportedAttributes'][ $block_type ] = $supported_block_attributes;
 		}
diff --git a/src/wp-includes/class-wp-block.php b/src/wp-includes/class-wp-block.php
index 8baf0f99bacde..cd975fd1d777a 100644
--- a/src/wp-includes/class-wp-block.php
+++ b/src/wp-includes/class-wp-block.php
@@ -65,6 +65,15 @@ class WP_Block {
 	 */
 	protected $registry;
 
+	/**
+	 * The blocks whose inner blocks a block bindings source supplied are
+	 * rendering, outermost first, each with the request it made to the source.
+	 *
+	 * @since 7.3.0
+	 * @var array[]
+	 */
+	private static $rendering_inner_blocks = array();
+
 	/**
 	 * List of inner blocks (of this same class)
 	 *
@@ -273,6 +282,8 @@ public function __get( $name ) {
 	 * @since 6.5.0
 	 * @since 6.6.0 Handle the `__default` attribute for pattern overrides.
 	 * @since 6.7.0 Return any updated bindings metadata in the computed attributes.
+	 * @since 7.3.0 Replace the inner blocks of the block for an `innerBlocks` binding,
+	 *              which the `__default` binding doesn't add.
 	 *
 	 * @return array The computed block attributes for the provided block bindings.
 	 */
@@ -310,6 +321,9 @@ private function process_block_bindings() {
 			 * resulting array.
 			 */
 			foreach ( $supported_block_attributes as $attribute_name ) {
+				if ( 'innerBlocks' === $attribute_name && ! isset( $bindings['innerBlocks'] ) ) {
+					continue;
+				}
 				// Retain any non-pattern override bindings that might be present.
 				$updated_bindings[ $attribute_name ] = $bindings[ $attribute_name ] ?? array( 'source' => 'core/pattern-overrides' );
 			}
@@ -348,7 +362,13 @@ private function process_block_bindings() {
 				}
 			}
 
-			$source_args  = ! empty( $block_binding['args'] ) && is_array( $block_binding['args'] ) ? $block_binding['args'] : array();
+			$source_args = ! empty( $block_binding['args'] ) && is_array( $block_binding['args'] ) ? $block_binding['args'] : array();
+
+			if ( 'innerBlocks' === $attribute_name ) {
+				$this->replace_inner_blocks( $block_binding_source, $source_args );
+				continue;
+			}
+
 			$source_value = $block_binding_source->get_value( $source_args, $this, $attribute_name );
 
 			// If the value is not null, process the HTML based on the block and the attribute.
@@ -360,6 +380,285 @@ private function process_block_bindings() {
 		return $computed_attributes;
 	}
 
+	/**
+	 * Replaces the inner blocks of the block with the ones a block bindings
+	 * source supplies, before they render.
+	 *
+	 * Not while the inner blocks the source supplied for the same request
+	 * render: the block then keeps its own inner blocks, and the source isn't
+	 * asked. This way sources whose values bind each other's, directly or
+	 * through content that loads as it renders, like the menu of a Navigation
+	 * block, can't render forever. Bindings that ask a source something else
+	 * still resolve, inside supplied inner blocks too.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @param WP_Block_Bindings_Source $source      The source of the binding.
+	 * @param array                    $source_args The arguments of the binding.
+	 */
+	private function replace_inner_blocks( WP_Block_Bindings_Source $source, array $source_args ) {
+		$request = $this->get_inner_blocks_request( $source, $source_args );
+		foreach ( self::$rendering_inner_blocks as $rendering ) {
+			if ( $rendering['request'] === $request ) {
+				return;
+			}
+		}
+
+		$value = $source->get_value( $source_args, $this, 'innerBlocks' );
+		if ( ! self::is_inner_blocks_value( $value ) ) {
+			return;
+		}
+
+		$blocks        = $this->parse_bound_inner_blocks( $value, $source, $source_args );
+		$inner_content = self::get_inner_content_with_slots( $this->parsed_block['innerContent'] ?? null, count( $blocks ) );
+		if ( null === $inner_content ) {
+			return;
+		}
+
+		$this->parsed_block['innerBlocks']  = $blocks;
+		$this->parsed_block['innerContent'] = $inner_content;
+		$this->parsed_block['innerHTML']    = implode( '', array_filter( $inner_content, 'is_string' ) );
+		$this->inner_blocks                 = new WP_Block_List( array() );
+		$this->inner_content                = $inner_content;
+		$this->inner_html                   = $this->parsed_block['innerHTML'];
+		$this->refresh_parsed_block_dependents();
+
+		self::$rendering_inner_blocks[] = array(
+			'block'   => $this,
+			'request' => $request,
+		);
+	}
+
+	/**
+	 * Returns what the block asks its block bindings source for `innerBlocks`:
+	 * the source, the arguments of the binding, the context the source uses,
+	 * and the attributes of the block.
+	 *
+	 * Two blocks with the same request get the same inner blocks from the
+	 * source.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @param WP_Block_Bindings_Source $source      The source of the binding.
+	 * @param array                    $source_args The arguments of the binding.
+	 * @return array The request.
+	 */
+	private function get_inner_blocks_request( WP_Block_Bindings_Source $source, array $source_args ): array {
+		$context = array();
+		foreach ( (array) $source->uses_context as $context_name ) {
+			if ( array_key_exists( $context_name, $this->context ) ) {
+				$context[ $context_name ] = $this->context[ $context_name ];
+			}
+		}
+		return array( $source->name, $source_args, $context, $this->attributes );
+	}
+
+	/**
+	 * Stops tracking the block, once it has rendered, if the inner blocks a
+	 * source supplied for it were rendering.
+	 *
+	 * The blocks still rendering inside it, if any, stopped with it: a block
+	 * that doesn't finish rendering, because of an exception, never gets here,
+	 * so they are forgotten along with it.
+	 *
+	 * @since 7.3.0
+	 */
+	private function forget_rendered_inner_blocks() {
+		foreach ( self::$rendering_inner_blocks as $index => $rendering ) {
+			if ( $rendering['block'] === $this ) {
+				self::$rendering_inner_blocks = array_slice( self::$rendering_inner_blocks, 0, $index );
+				return;
+			}
+		}
+	}
+
+	/**
+	 * Determines whether the value of a block bindings source supplies inner
+	 * blocks.
+	 *
+	 * Serialized block markup supplies them, and an empty string supplies none.
+	 * Markup supplies them when the first block delimiter the block parser
+	 * finds, after any whitespace, opens a block. Any other value, like the
+	 * plain text of a field, leaves the block with its own inner blocks.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @param mixed $value The value of the source.
+	 * @return bool Whether the value supplies inner blocks.
+	 */
+	private static function is_inner_blocks_value( $value ): bool {
+		if ( '' === $value ) {
+			return true;
+		}
+		if ( ! is_string( $value ) ) {
+			return false;
+		}
+
+		$processor = new WP_Block_Processor( $value );
+		while ( $processor->next_token() ) {
+			if ( $processor->is_html() && ! $processor->is_non_whitespace_html() ) {
+				continue;
+			}
+			return ! $processor->is_html() && $processor->opens_block();
+		}
+		return false;
+	}
+
+	/**
+	 * Parses the inner blocks a block bindings source supplies.
+	 *
+	 * The markup never went through the filters that sanitize post content on
+	 * save, and the user who supplied it may not be allowed unfiltered HTML, so
+	 * by default it is sanitized as on save, attributes of its blocks included.
+	 * Its embeds are expanded as the embeds of the content were, before its
+	 * blocks render.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @global WP_Embed $wp_embed WordPress Embed object.
+	 *
+	 * @param string                   $markup      The serialized blocks.
+	 * @param WP_Block_Bindings_Source $source      The source of the binding.
+	 * @param array                    $source_args The arguments of the binding.
+	 * @return array[] The parsed blocks.
+	 */
+	private function parse_bound_inner_blocks( string $markup, WP_Block_Bindings_Source $source, array $source_args ): array {
+		global $wp_embed;
+
+		/**
+		 * Filters whether the inner blocks a block bindings source supplies are
+		 * sanitized before they render.
+		 *
+		 * By default the markup is sanitized as the post content of a user
+		 * without the `unfiltered_html` capability, since the user who supplied
+		 * it is unknown: `wp_kses_post()` removes the HTML that user may not
+		 * publish, in the attributes of the blocks included. A source whose
+		 * markup comes from trusted code, not from users, may keep it as
+		 * supplied. Custom CSS is removed from the blocks either way.
+		 *
+		 * Sanitizing keeps the block delimiters that `serialize_blocks()`
+		 * writes, which escapes the characters `wp_kses_post()` rewrites
+		 * inside comments.
+		 *
+		 * @since 7.3.0
+		 *
+		 * @param bool     $sanitize       Whether to sanitize the markup. Default true.
+		 * @param string   $source_name    The name of the source.
+		 * @param array    $source_args    The arguments of the binding.
+		 * @param WP_Block $block_instance The block whose inner blocks the source supplies.
+		 */
+		if ( apply_filters( 'block_bindings_sanitize_inner_blocks', true, $source->name, $source_args, $this ) ) {
+			$markup = wp_kses_post( $markup );
+		}
+		if ( $wp_embed instanceof WP_Embed ) {
+			$markup = $wp_embed->run_shortcode( $markup );
+			$markup = $wp_embed->autoembed( $markup );
+		}
+
+		return self::prepare_bound_inner_blocks( parse_blocks( $markup ) );
+	}
+
+	/**
+	 * Prepares the blocks a block bindings source supplies, and their inner
+	 * blocks, to render.
+	 *
+	 * Removes their custom CSS, which only users who can edit CSS may add:
+	 * whoever supplied the value is unknown.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @param array[] $blocks The parsed blocks.
+	 * @return array[] The parsed blocks.
+	 */
+	private static function prepare_bound_inner_blocks( array $blocks ): array {
+		foreach ( $blocks as &$block ) {
+			if ( isset( $block['attrs']['style'] ) ) {
+				$block['attrs']['style'] = wp_strip_custom_css_from_style_array( $block['attrs']['style'] );
+				if ( empty( $block['attrs']['style'] ) ) {
+					unset( $block['attrs']['style'] );
+				}
+			}
+
+			$block['innerBlocks'] = self::prepare_bound_inner_blocks( $block['innerBlocks'] );
+		}
+		return $blocks;
+	}
+
+	/**
+	 * Returns the inner content of a block with slots for the given number of
+	 * inner blocks.
+	 *
+	 * The slots replace the block's own inner blocks and the HTML between them.
+	 * A block without inner blocks gets them before the closing tag of the
+	 * element that wraps its content.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @param array|null $inner_content The inner content of the block.
+	 * @param int        $count         The number of inner blocks.
+	 * @return array|null The inner content, or null if there's no element to put
+	 *                    the inner blocks in.
+	 */
+	private static function get_inner_content_with_slots( $inner_content, int $count ): ?array {
+		if ( ! is_array( $inner_content ) ) {
+			return null;
+		}
+
+		$slots     = array_fill( 0, $count, null );
+		$own_slots = array_keys( $inner_content, null, true );
+		if ( $own_slots ) {
+			$before_first_slot = array_slice( $inner_content, 0, $own_slots[0] );
+			$after_last_slot   = array_slice( $inner_content, end( $own_slots ) + 1 );
+			return array_merge( $before_first_slot, $slots, $after_last_slot );
+		}
+
+		$wrapper_parts = self::split_at_wrapper_closer( implode( '', $inner_content ) );
+		if ( null === $wrapper_parts ) {
+			return null;
+		}
+		return array_merge( array( $wrapper_parts[0] ), $slots, array( $wrapper_parts[1] ) );
+	}
+
+	/**
+	 * Splits the HTML of an element that wraps a block's content before the
+	 * element's closing tag.
+	 *
+	 * @since 7.3.0
+	 *
+	 * @param string $html The HTML of the wrapper element.
+	 * @return string[]|null The HTML before the closing tag and the HTML from it,
+	 *                       or null if the HTML has no wrapper element to split.
+	 */
+	private static function split_at_wrapper_closer( string $html ): ?array {
+		$processor = WP_HTML_Processor::create_fragment( $html );
+		if ( null === $processor ) {
+			return null;
+		}
+
+		$before                = '';
+		$after                 = '';
+		$depth_outside_wrapper = null;
+		$is_at_wrapper_closer  = false;
+		while ( $processor->next_token() ) {
+			if ( null === $depth_outside_wrapper && '#tag' === $processor->get_token_type() && ! $processor->is_tag_closer() ) {
+				$depth_outside_wrapper = $processor->get_current_depth() - 1;
+			} elseif ( $processor->is_tag_closer() && $processor->get_current_depth() === $depth_outside_wrapper ) {
+				$is_at_wrapper_closer = true;
+			}
+
+			if ( $is_at_wrapper_closer ) {
+				$after .= $processor->serialize_token();
+			} else {
+				$before .= $processor->serialize_token();
+			}
+		}
+
+		if ( ! $is_at_wrapper_closer || null !== $processor->get_last_error() || $processor->paused_at_incomplete_token() ) {
+			return null;
+		}
+		return array( $before, $after );
+	}
+
 	/**
 	 * Depending on the block attribute name, replace its value in the HTML based on the value provided.
 	 *
@@ -704,6 +1003,8 @@ public function render( $options = array() ) {
 			}
 		}
 
+		$this->forget_rendered_inner_blocks();
+
 		/**
 		 * Filters the content of a single block.
 		 *
diff --git a/tests/phpunit/tests/block-bindings/innerBlocks.php b/tests/phpunit/tests/block-bindings/innerBlocks.php
new file mode 100644
index 0000000000000..bbb4c5adaf52b
--- /dev/null
+++ b/tests/phpunit/tests/block-bindings/innerBlocks.php
@@ -0,0 +1,603 @@
+<?php
+/**
+ * Tests for the inner blocks bindings of the Group and Column blocks.
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ * @since 7.3.0
+ *
+ * @group blocks
+ * @group block-bindings
+ *
+ * @covers WP_Block::process_block_bindings
+ * @covers WP_Block::replace_inner_blocks
+ */
+class Tests_Block_Bindings_InnerBlocks extends WP_UnitTestCase {
+
+	const SOURCE = 'test/inner-blocks';
+
+	/**
+	 * The value the test source returns for `innerBlocks`, or a callable that
+	 * returns it from the arguments of the binding and the block instance.
+	 *
+	 * @var mixed
+	 */
+	private $value;
+
+	/**
+	 * The number of times the test source supplied `innerBlocks`.
+	 *
+	 * @var int
+	 */
+	private $inner_blocks_calls;
+
+	public function set_up() {
+		parent::set_up();
+		$this->value              = null;
+		$this->inner_blocks_calls = 0;
+		register_block_bindings_source(
+			self::SOURCE,
+			array(
+				'label'              => 'Test',
+				'get_value_callback' => function ( $source_args, $block_instance, $attribute_name ) {
+					if ( 'innerBlocks' !== $attribute_name ) {
+						return 'Bound text';
+					}
+					++$this->inner_blocks_calls;
+					return $this->value instanceof Closure ? call_user_func( $this->value, $source_args, $block_instance ) : $this->value;
+				},
+			)
+		);
+	}
+
+	public function tear_down() {
+		unregister_block_bindings_source( self::SOURCE );
+		parent::tear_down();
+	}
+
+	/**
+	 * Renders a Group block with the given bindings and, by default, a
+	 * `Default` paragraph as its own inner blocks.
+	 *
+	 * @param array|null $bindings   The bindings of the Group block.
+	 * @param string     $inner_html The markup inside the Group's wrapper.
+	 * @return string The rendered block.
+	 */
+	private function render_group( $bindings = null, $inner_html = '<!-- wp:paragraph --><p>Default</p><!-- /wp:paragraph -->' ) {
+		$bindings = $bindings ?? array( 'innerBlocks' => array( 'source' => self::SOURCE ) );
+		$markup   = '<!-- wp:group {"metadata":{"bindings":' . wp_json_encode( $bindings ) . '}} -->';
+		$markup  .= '<div class="wp-block-group">' . $inner_html . '</div>';
+		$markup  .= '<!-- /wp:group -->';
+		$block    = new WP_Block( parse_blocks( $markup )[0] );
+		return $block->render();
+	}
+
+	/**
+	 * Returns the markup of a Group block bound to the test source, with a
+	 * paragraph of its own.
+	 *
+	 * @param array  $args The arguments of the binding.
+	 * @param string $own  The text of the Group's own paragraph.
+	 * @return string The markup.
+	 */
+	private function bound_group_markup( $args = array(), $own = 'Nested own' ) {
+		$binding = array( 'source' => self::SOURCE );
+		if ( $args ) {
+			$binding['args'] = $args;
+		}
+		return '<!-- wp:group {"metadata":{"bindings":{"innerBlocks":' . wp_json_encode( $binding ) . '}}} --><div class="wp-block-group"><!-- wp:paragraph --><p>' . $own . '</p><!-- /wp:paragraph --></div><!-- /wp:group -->';
+	}
+
+	/**
+	 * Returns the attributes the supplied blocks render with.
+	 *
+	 * @return array[] The attributes of each rendered block, in render order.
+	 */
+	private function render_group_and_get_supplied_attributes() {
+		$attributes = array();
+		$capture    = static function ( $parsed_block, $source_block, $parent_block ) use ( &$attributes ) {
+			if ( $parent_block ) {
+				$attributes[] = $parsed_block['attrs'];
+			}
+			return $parsed_block;
+		};
+		add_filter( 'render_block_data', $capture, 10, 3 );
+		$this->render_group();
+		remove_filter( 'render_block_data', $capture );
+		return $attributes;
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_replaces_inner_blocks() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph --><!-- wp:paragraph --><p>Two</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group();
+		$this->assertStringContainsString( '>One</p><p', $output );
+		$this->assertStringContainsString( '>Two</p></div>', $output );
+		$this->assertStringNotContainsString( 'Default', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_may_start_with_whitespace() {
+		$this->value = "\n\t<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->";
+		$this->assertStringContainsString( '>One</p>', $this->render_group() );
+	}
+
+	/**
+	 * @ticket 66415
+	 *
+	 * @dataProvider data_whitespace_after_the_delimiter_opener
+	 *
+	 * @param string $whitespace The whitespace between `<!--` and `wp:`.
+	 */
+	public function test_value_may_have_any_whitespace_after_the_delimiter_opener( $whitespace ) {
+		$this->value = "<!--{$whitespace}wp:paragraph --><p>One</p><!-- /wp:paragraph -->";
+		$output      = $this->render_group();
+		$this->assertStringContainsString( '>One</p>', $output );
+		$this->assertStringNotContainsString( 'Default', $output );
+	}
+
+	public function data_whitespace_after_the_delimiter_opener() {
+		return array(
+			'space'   => array( ' ' ),
+			'tab'     => array( "\t" ),
+			'newline' => array( "\n" ),
+		);
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_whitespace_value_keeps_own_inner_blocks() {
+		$this->value = " \n\t";
+		$this->assertStringContainsString( '>Default</p>', $this->render_group() );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_starting_with_a_closer_keeps_own_inner_blocks() {
+		$this->value = '<!-- /wp:paragraph --><!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$this->assertStringContainsString( '>Default</p>', $this->render_group() );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_empty_value_removes_inner_blocks() {
+		$this->value = '';
+		$output      = $this->render_group();
+		$this->assertStringNotContainsString( '<p', $output );
+		$this->assertStringContainsString( 'wp-block-group', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_empty_value_removes_inner_blocks_without_wrapper_markup() {
+		$this->value = '';
+		$output      = render_block( parse_blocks( '<!-- wp:group {"metadata":{"bindings":{"innerBlocks":{"source":"' . self::SOURCE . '"}}}} --><!-- wp:paragraph --><p>Default</p><!-- /wp:paragraph --><!-- /wp:group -->' )[0] );
+		$this->assertSame( '', $output );
+	}
+
+	public function test_without_value_keeps_own_inner_blocks() {
+		$this->assertStringContainsString( '>Default</p>', $this->render_group() );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_plain_text_value_keeps_own_inner_blocks() {
+		$this->value = 'Plain text';
+		$output      = $this->render_group();
+		$this->assertStringContainsString( '>Default</p>', $output );
+		$this->assertStringNotContainsString( 'Plain text', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_does_not_become_an_attribute() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$block       = new WP_Block( parse_blocks( '<!-- wp:group {"metadata":{"bindings":{"innerBlocks":{"source":"test/inner-blocks"}}}} --><div class="wp-block-group"></div><!-- /wp:group -->' )[0] );
+		$block->render();
+		$this->assertArrayNotHasKey( 'innerBlocks', $block->attributes );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_default_pattern_overrides_binding_does_not_bind_inner_blocks() {
+		$requested = array();
+		$record    = static function ( $value, $source_name, $source_args, $block_instance, $attribute_name ) use ( &$requested ) {
+			$requested[] = $attribute_name;
+			return $value;
+		};
+		add_filter( 'block_bindings_source_value', $record, 10, 5 );
+		$output = $this->render_group( array( '__default' => array( 'source' => 'core/pattern-overrides' ) ) );
+		remove_filter( 'block_bindings_source_value', $record );
+
+		$this->assertNotContains( 'innerBlocks', $requested );
+		$this->assertSame( $this->render_group( array() ), $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_is_sanitized() {
+		$this->value = '<!-- wp:html --><script>alert(1)</script><p>Safe</p><!-- /wp:html -->';
+		$output      = $this->render_group();
+		$this->assertStringNotContainsString( '<script>', $output );
+		$this->assertStringContainsString( '<p>Safe</p>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_block_attributes_in_the_value_are_sanitized() {
+		$this->value = '<!-- wp:paragraph {"className":"<img src=x onerror=alert(1)>"} --><p>Safe</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group();
+		$this->assertStringNotContainsString( 'onerror', $output );
+		$this->assertStringContainsString( '>Safe</p>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_of_a_trusted_source_is_not_sanitized() {
+		$this->value = '<!-- wp:html --><svg><circle r="1"></circle></svg><!-- /wp:html -->';
+		$trusted     = array();
+		$trust       = static function ( $sanitize, $source_name, $source_args, $block_instance ) use ( &$trusted ) {
+			$trusted[] = array( $source_name, $source_args, $block_instance->name );
+			return false;
+		};
+		add_filter( 'block_bindings_sanitize_inner_blocks', $trust, 10, 4 );
+		$output = $this->render_group(
+			array(
+				'innerBlocks' => array(
+					'source' => self::SOURCE,
+					'args'   => array( 'key' => 'chart' ),
+				),
+			)
+		);
+		remove_filter( 'block_bindings_sanitize_inner_blocks', $trust );
+
+		$this->assertStringContainsString( '<svg><circle r="1"></circle></svg>', $output );
+		$this->assertSame( array( array( self::SOURCE, array( 'key' => 'chart' ), 'core/group' ) ), $trusted );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_custom_css_in_the_value_of_a_trusted_source_is_removed() {
+		$this->value = '<!-- wp:paragraph {"style":{"css":"color:red"}} --><p>Styled</p><!-- /wp:paragraph -->';
+		add_filter( 'block_bindings_sanitize_inner_blocks', '__return_false' );
+		$output = $this->render_group();
+		remove_filter( 'block_bindings_sanitize_inner_blocks', '__return_false' );
+
+		$this->assertStringNotContainsString( 'wp-custom-css-', $output );
+		$this->assertStringContainsString( '>Styled</p>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_bindings_to_the_same_source_inside_the_value_are_ignored() {
+		$this->value = $this->bound_group_markup();
+		$output      = $this->render_group();
+		$this->assertStringContainsString( '>Nested own</p>', $output );
+		$this->assertSame( 2, substr_count( $output, '<div class="wp-block-group">' ) );
+		$this->assertSame( 1, $this->inner_blocks_calls );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_sources_binding_each_other_render_once() {
+		register_block_bindings_source(
+			'test/other-inner-blocks',
+			array(
+				'label'              => 'Test',
+				'get_value_callback' => function () {
+					return $this->bound_group_markup( array(), 'From other' );
+				},
+			)
+		);
+		$this->value = '<!-- wp:group {"metadata":{"bindings":{"innerBlocks":{"source":"test/other-inner-blocks"}}}} --><div class="wp-block-group"><!-- wp:paragraph --><p>From test</p><!-- /wp:paragraph --></div><!-- /wp:group -->';
+		$output      = $this->render_group();
+		unregister_block_bindings_source( 'test/other-inner-blocks' );
+		$this->assertStringContainsString( '>From other</p>', $output );
+		$this->assertStringNotContainsString( 'From test', $output );
+		$this->assertStringNotContainsString( 'Default', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_bindings_to_another_source_inside_the_value_resolve() {
+		register_block_bindings_source(
+			'test/other-inner-blocks',
+			array(
+				'label'              => 'Test',
+				'get_value_callback' => static function () {
+					return '<!-- wp:paragraph --><p>From other</p><!-- /wp:paragraph -->';
+				},
+			)
+		);
+		$this->value = '<!-- wp:group {"metadata":{"bindings":{"innerBlocks":{"source":"test/other-inner-blocks"}}}} --><div class="wp-block-group"><!-- wp:paragraph --><p>Nested own</p><!-- /wp:paragraph --></div><!-- /wp:group -->';
+		$output      = $this->render_group();
+		unregister_block_bindings_source( 'test/other-inner-blocks' );
+		$this->assertStringContainsString( '>From other</p>', $output );
+		$this->assertStringNotContainsString( 'Nested own', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_bindings_with_other_arguments_inside_the_value_resolve() {
+		$this->value = function ( $source_args ) {
+			$level = $source_args['level'] ?? 1;
+			if ( $level < 3 ) {
+				return $this->bound_group_markup( array( 'level' => $level + 1 ), "Level {$level} own" );
+			}
+			return '<!-- wp:paragraph --><p>Level 3</p><!-- /wp:paragraph -->';
+		};
+		$output      = $this->render_group();
+		$this->assertStringContainsString( '>Level 3</p>', $output );
+		$this->assertStringNotContainsString( 'own', $output );
+		$this->assertSame( 3, $this->inner_blocks_calls );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_bindings_with_other_attributes_inside_the_value_resolve() {
+		$this->value = '<!-- wp:group {"tagName":"section","metadata":{"bindings":{"innerBlocks":{"source":"' . self::SOURCE . '"}}}} --><section class="wp-block-group"><!-- wp:paragraph --><p>Nested own</p><!-- /wp:paragraph --></section><!-- /wp:group -->';
+		$output      = $this->render_group();
+		$this->assertSame( 2, substr_count( $output, '<section class="wp-block-group">' ) );
+		$this->assertSame( 1, substr_count( $output, 'Nested own' ) );
+	}
+
+	public function test_bindings_with_other_context_inside_the_value_resolve() {
+		register_block_type(
+			'test/provides-post',
+			array(
+				'attributes'       => array( 'id' => array( 'type' => 'integer' ) ),
+				'provides_context' => array( 'postId' => 'id' ),
+			)
+		);
+		register_block_bindings_source(
+			'test/post-inner-blocks',
+			array(
+				'label'              => 'Test',
+				'uses_context'       => array( 'postId' ),
+				'get_value_callback' => static function ( $source_args, $block_instance ) {
+					if ( 1 === $block_instance->context['postId'] ) {
+						return '<!-- wp:test/provides-post {"id":2} --><!-- wp:group {"metadata":{"bindings":{"innerBlocks":{"source":"test/post-inner-blocks"}}}} --><div class="wp-block-group"><!-- wp:paragraph --><p>Nested own</p><!-- /wp:paragraph --></div><!-- /wp:group --><!-- /wp:test/provides-post -->';
+					}
+					return '<!-- wp:paragraph --><p>Post ' . $block_instance->context['postId'] . '</p><!-- /wp:paragraph -->';
+				},
+			)
+		);
+		$output = do_blocks( '<!-- wp:test/provides-post {"id":1} --><!-- wp:group {"metadata":{"bindings":{"innerBlocks":{"source":"test/post-inner-blocks"}}}} --><div class="wp-block-group"><!-- wp:paragraph --><p>Default</p><!-- /wp:paragraph --></div><!-- /wp:group --><!-- /wp:test/provides-post -->' );
+		unregister_block_bindings_source( 'test/post-inner-blocks' );
+		unregister_block_type( 'test/provides-post' );
+
+		$this->assertStringContainsString( '>Post 2</p>', $output );
+		$this->assertStringNotContainsString( 'Nested own', $output );
+		$this->assertStringNotContainsString( 'Default', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_bindings_inside_content_loaded_by_the_value_are_ignored() {
+		register_block_type(
+			'test/loads-content',
+			array(
+				'render_callback' => function () {
+					return do_blocks( $this->bound_group_markup( array(), 'Loaded own' ) );
+				},
+			)
+		);
+		$this->value = '<!-- wp:test/loads-content /-->';
+		$output      = $this->render_group();
+		unregister_block_type( 'test/loads-content' );
+
+		$this->assertSame( 1, $this->inner_blocks_calls );
+		$this->assertSame( 1, substr_count( $output, 'Loaded own' ) );
+		$this->assertStringNotContainsString( 'Default', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_sibling_bindings_each_resolve() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$group       = $this->bound_group_markup( array(), 'Default' );
+		$output      = do_blocks( $group . $group );
+
+		$this->assertSame( 2, $this->inner_blocks_calls );
+		$this->assertSame( 2, substr_count( $output, '>One</p>' ) );
+		$this->assertStringNotContainsString( 'Default', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_bindings_resolve_again_after_supplied_inner_blocks_render() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$this->render_group();
+		$this->assertStringContainsString( '>One</p>', $this->render_group() );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_blocks_that_stop_rendering_inside_a_host_are_forgotten_with_it() {
+		register_block_type(
+			'test/throws',
+			array(
+				'render_callback' => static function () {
+					throw new Exception( 'Stopped' );
+				},
+			)
+		);
+		register_block_type(
+			'test/catches',
+			array(
+				'render_callback' => function () {
+					try {
+						return do_blocks( $this->bound_group_markup( array( 'part' => 'inner' ) ) );
+					} catch ( Exception $exception ) {
+						return $exception->getMessage();
+					}
+				},
+			)
+		);
+		$this->value = static function ( $source_args ) {
+			return 'inner' === ( $source_args['part'] ?? '' ) ? '<!-- wp:test/throws /-->' : '<!-- wp:test/catches /-->';
+		};
+		$output      = $this->render_group();
+		$this->assertStringContainsString( 'Stopped', $output );
+
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group(
+			array(
+				'innerBlocks' => array(
+					'source' => self::SOURCE,
+					'args'   => array( 'part' => 'inner' ),
+				),
+			)
+		);
+		unregister_block_type( 'test/throws' );
+		unregister_block_type( 'test/catches' );
+
+		$this->assertStringContainsString( '>One</p>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_attribute_bindings_inside_the_value_are_kept() {
+		$this->value = '<!-- wp:paragraph {"metadata":{"bindings":{"content":{"source":"test/inner-blocks"}}}} --><p>One</p><!-- /wp:paragraph -->';
+		$this->assertStringContainsString( '>Bound text</p>', $this->render_group() );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_custom_css_in_the_value_is_removed() {
+		$this->value = '<!-- wp:paragraph {"style":{"css":"color:red","color":{"text":"#00f"},":hover":{"css":"color:green"}}} --><p>Styled</p><!-- /wp:paragraph -->';
+		$attributes  = $this->render_group_and_get_supplied_attributes();
+		$this->assertSame( array( 'color' => array( 'text' => '#00f' ) ), $attributes[0]['style'] );
+		$this->assertStringNotContainsString( 'wp-custom-css-', $this->render_group() );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_nested_custom_css_in_the_value_is_removed() {
+		$this->value = '<!-- wp:group --><div class="wp-block-group"><!-- wp:paragraph {"style":{"@mobile":{":hover":{"css":"color:red"}}}} --><p>Styled</p><!-- /wp:paragraph --></div><!-- /wp:group -->';
+		$output      = $this->render_group();
+		$this->assertStringNotContainsString( 'wp-custom-css-', $output );
+		$this->assertStringContainsString( '>Styled</p>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_goes_where_the_own_inner_blocks_were() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group( null, '<!-- wp:paragraph --><p>Default</p><!-- /wp:paragraph --><span>Tail</span>' );
+		$this->assertStringContainsString( '>One</p><span>Tail</span>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_goes_inside_the_inner_container_of_a_legacy_group() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group( null, '<div class="wp-block-group__inner-container"><!-- wp:paragraph --><p>Default</p><!-- /wp:paragraph --></div>' );
+		$this->assertSame( 1, substr_count( $output, 'wp-block-group__inner-container' ) );
+		$this->assertStringEndsWith( '>One</p></div></div>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_goes_inside_an_empty_group() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group( null, '' );
+		$this->assertStringStartsWith( '<div class="wp-block-group', $output );
+		$this->assertStringContainsString( '>One</p></div>', $output );
+		$this->assertSame( 1, substr_count( $output, '<p' ) );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_goes_before_the_closer_of_a_wrapper_with_unclosed_elements() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group( null, '<p>Tail' );
+		$this->assertStringContainsString( '<p>Tail</p><p', $output );
+		$this->assertStringContainsString( '>One</p></div>', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_value_is_skipped_without_markup_to_place_it_in() {
+		$this->value = '<!-- wp:paragraph --><p>One</p><!-- /wp:paragraph -->';
+		$output      = render_block(
+			array(
+				'blockName'   => 'core/group',
+				'attrs'       => array( 'metadata' => array( 'bindings' => array( 'innerBlocks' => array( 'source' => self::SOURCE ) ) ) ),
+				'innerBlocks' => array(),
+			)
+		);
+		$this->assertSame( '', $output );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_column_supports_inner_blocks_bindings() {
+		$this->assertContains( 'innerBlocks', get_block_bindings_supported_attributes( 'core/column' ) );
+		$this->assertContains( 'innerBlocks', get_block_bindings_supported_attributes( 'core/group' ) );
+	}
+
+	/**
+	 * @ticket 66415
+	 *
+	 * @covers ::get_block_editor_settings
+	 */
+	public function test_editor_does_not_offer_inner_blocks_bindings() {
+		$settings = get_block_editor_settings( array(), new WP_Block_Editor_Context() );
+		$this->assertArrayNotHasKey( 'core/group', $settings['__experimentalBlockBindingsSupportedAttributes'] );
+		$this->assertArrayNotHasKey( 'core/column', $settings['__experimentalBlockBindingsSupportedAttributes'] );
+		$this->assertSame( array( 'content' ), $settings['__experimentalBlockBindingsSupportedAttributes']['core/paragraph'] );
+	}
+
+	/**
+	 * @ticket 66415
+	 */
+	public function test_embeds_in_the_value_are_rendered() {
+		wp_embed_register_handler(
+			'test-inner-blocks',
+			'#https://example\.org/video/(\w+)#',
+			static function ( $matches ) {
+				return '<iframe class="test-embed" src="https://example.org/embed/' . $matches[1] . '"></iframe>';
+			}
+		);
+		$this->value = '<!-- wp:paragraph --><p>[embed]https://example.org/video/one[/embed]</p><!-- /wp:paragraph --><!-- wp:paragraph --><p>https://example.org/video/two</p><!-- /wp:paragraph -->';
+		$output      = $this->render_group();
+		wp_embed_unregister_handler( 'test-inner-blocks' );
+
+		$this->assertStringContainsString( '<iframe class="test-embed" src="https://example.org/embed/one"></iframe>', $output );
+		$this->assertStringContainsString( '<iframe class="test-embed" src="https://example.org/embed/two"></iframe>', $output );
+	}
+}