diff --git a/src/Integrations/Divi/BlockTree/Block.php b/src/Integrations/Divi/BlockTree/Block.php
new file mode 100644
index 0000000..532f8ae
--- /dev/null
+++ b/src/Integrations/Divi/BlockTree/Block.php
@@ -0,0 +1,137 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\BlockTree;
+
+/**
+ * One block of the tree. A parsed block keeps its original opener/closer bytes; they are
+ * dropped only when the block itself changes (setAttrs(), a void block getting children),
+ * so the Serializer regenerates exactly the changed openers and nothing else.
+ *
+ * Opaque blocks (attributes that are no JSON object, divi/global-layout, anything carrying
+ * globalModule) are never regenerated and never descended into by the tools – Divi's own
+ * code warns that parse_blocks() mishandles global modules; Etappe 3 edits them.
+ */
+final class Block extends Container
+{
+    /**
+     * @param array<string, mixed> $attrs
+     */
+    private function __construct(
+        private string $name,
+        private array $attrs,
+        private ?string $rawOpen,
+        private ?string $rawClose,
+        private bool $void,
+        private bool $opaque
+    ) {
+    }
+
+    /** @param array<string, mixed> $attrs */
+    public static function parsed(string $name, array $attrs, string $rawOpen, bool $void, bool $opaque): self
+    {
+        return new self($name, $attrs, $rawOpen, null, $void, $opaque);
+    }
+
+    /**
+     * A new block (opener and closer are generated; written as a pair like Divi does).
+     *
+     * @param array<string, mixed> $attrs
+     * @param list<Block>          $children
+     */
+    public static function create(string $name, array $attrs = [], array $children = []): self
+    {
+        $block = new self($name, $attrs, null, null, false, false);
+        foreach ($children as $child) {
+            $block->parts[] = $child;
+        }
+
+        return $block;
+    }
+
+    /** Used by the Parser for the closing delimiter. */
+    public function closeWith(string $rawClose): void
+    {
+        $this->rawClose = $rawClose;
+    }
+
+    /** Full block name, e.g. "divi/section"; blocks without namespace are "core/…". */
+    public function name(): string
+    {
+        return $this->name;
+    }
+
+    /** Name without the "divi/" namespace, e.g. "button"; other namespaces stay. */
+    public function shortName(): string
+    {
+        return str_starts_with($this->name, 'divi/') ? substr($this->name, 5) : $this->name;
+    }
+
+    /** @return array<string, mixed> */
+    public function attrs(): array
+    {
+        return $this->attrs;
+    }
+
+    /** @param array<string, mixed> $attrs */
+    public function setAttrs(array $attrs): void
+    {
+        $this->attrs = $attrs;
+        $this->rawOpen = null;
+    }
+
+    public function rawOpen(): ?string
+    {
+        return $this->rawOpen;
+    }
+
+    public function rawClose(): ?string
+    {
+        return $this->rawClose;
+    }
+
+    public function isVoid(): bool
+    {
+        return $this->void;
+    }
+
+    public function isOpaque(): bool
+    {
+        return $this->opaque;
+    }
+
+    public function isDivi(): bool
+    {
+        return str_starts_with($this->name, 'divi/');
+    }
+
+    /** A global module reference or global layout (edited only in Etappe 3). */
+    public function isGlobal(): bool
+    {
+        return $this->name === 'divi/global-layout' || array_key_exists('globalModule', $this->attrs);
+    }
+
+    /** Deep copy – unchanged copies serialize to exactly the same bytes. */
+    public function copy(): self
+    {
+        return clone $this;
+    }
+
+    public function __clone()
+    {
+        foreach ($this->parts as $position => $part) {
+            if ($part instanceof Block) {
+                $this->parts[$position] = clone $part;
+            }
+        }
+    }
+
+    protected function touched(): void
+    {
+        if ($this->void) {
+            $this->void = false;
+            $this->rawOpen = null;
+        }
+    }
+}
diff --git a/src/Integrations/Divi/BlockTree/Container.php b/src/Integrations/Divi/BlockTree/Container.php
new file mode 100644
index 0000000..08cd5f1
--- /dev/null
+++ b/src/Integrations/Divi/BlockTree/Container.php
@@ -0,0 +1,93 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\BlockTree;
+
+use InvalidArgumentException;
+
+/**
+ * Ordered parts of a document or of a block's inner content: blocks and the raw text
+ * between them (whitespace, freeform HTML, Divi 4 shortcodes). Keeping every byte of that
+ * text is what makes parse → serialize byte-identical (spec §5.2).
+ */
+abstract class Container
+{
+    /** @var list<string|Block> */
+    protected array $parts = [];
+
+    /** @return list<string|Block> */
+    public function parts(): array
+    {
+        return $this->parts;
+    }
+
+    /** @return list<Block> */
+    public function children(): array
+    {
+        return array_values(array_filter($this->parts, static fn (string|Block $part): bool => $part instanceof Block));
+    }
+
+    /** Used by the Parser: adds a part without marking the container as changed. */
+    public function append(string|Block $part): void
+    {
+        $this->parts[] = $part;
+    }
+
+    /** Child position of $block (0-based among the child blocks), null when it is no child. */
+    public function indexOf(Block $block): ?int
+    {
+        $index = array_search($block, $this->children(), true);
+
+        return $index === false ? null : (int) $index;
+    }
+
+    /**
+     * Inserts $block so it becomes child number $index (0 = first; count or more = after the
+     * last child). Text between existing children stays where it is.
+     */
+    public function insertChild(int $index, Block $block): void
+    {
+        $children = $this->children();
+        $index = max(0, min($index, count($children)));
+        if ($index < count($children)) {
+            $position = $this->partPosition($children[$index]);
+        } elseif ($children === []) {
+            $position = count($this->parts);
+        } else {
+            $position = $this->partPosition($children[count($children) - 1]) + 1;
+        }
+
+        array_splice($this->parts, $position, 0, [$block]);
+        $this->touched();
+    }
+
+    /** Removes the child block; the text around it stays. Returns its former child index. */
+    public function removeChild(Block $block): int
+    {
+        $index = $this->indexOf($block);
+        if ($index === null) {
+            throw new InvalidArgumentException('Block is not a child of this container.');
+        }
+
+        array_splice($this->parts, $this->partPosition($block), 1);
+        $this->touched();
+
+        return $index;
+    }
+
+    /** Called after the list of children changed. */
+    protected function touched(): void
+    {
+    }
+
+    private function partPosition(Block $block): int
+    {
+        $position = array_search($block, $this->parts, true);
+        if ($position === false) {
+            throw new InvalidArgumentException('Block is not a child of this container.');
+        }
+
+        return (int) $position;
+    }
+}
diff --git a/src/Integrations/Divi/BlockTree/Document.php b/src/Integrations/Divi/BlockTree/Document.php
new file mode 100644
index 0000000..49849ac
--- /dev/null
+++ b/src/Integrations/Divi/BlockTree/Document.php
@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\BlockTree;
+
+/**
+ * The parsed post_content: top-level blocks and the text between them.
+ */
+final class Document extends Container
+{
+}
diff --git a/src/Integrations/Divi/BlockTree/Json.php b/src/Integrations/Divi/BlockTree/Json.php
new file mode 100644
index 0000000..f865d34
--- /dev/null
+++ b/src/Integrations/Divi/BlockTree/Json.php
@@ -0,0 +1,61 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\BlockTree;
+
+use JsonException;
+use stdClass;
+
+/**
+ * JSON of block attributes. PHP arrays cannot tell an empty JSON object from an empty list,
+ * nor an object with the keys "0", "1", … from a list. decodeObject() therefore keeps such
+ * objects as stdClass, so a regenerated opener encodes them as {} again (Divi breaks on
+ * "[]" where it expects "{}" – see its EmptyArrayCorruptionMigration).
+ */
+final class Json
+{
+    /** @return array<string, mixed>|null Null when $json is not a JSON object. */
+    public static function decodeObject(string $json): ?array
+    {
+        try {
+            $value = json_decode($json, false, 512, JSON_THROW_ON_ERROR);
+        } catch (JsonException) {
+            return null;
+        }
+
+        if (! $value instanceof stdClass) {
+            return null;
+        }
+
+        $converted = self::fromJson($value);
+
+        return is_array($converted) ? $converted : [];
+    }
+
+    /** Converts json_decode(…, false) output: objects become arrays unless that would lose their object-ness. */
+    public static function fromJson(mixed $value): mixed
+    {
+        if ($value instanceof stdClass) {
+            $array = [];
+            foreach (get_object_vars($value) as $key => $item) {
+                $array[$key] = self::fromJson($item);
+            }
+
+            return $array === [] || array_is_list($array) ? (object) $array : $array;
+        }
+
+        if (is_array($value)) {
+            return array_map([self::class, 'fromJson'], $value);
+        }
+
+        return $value;
+    }
+
+    /** @throws JsonException */
+    public static function encode(mixed $value): string
+    {
+        // phpcs:ignore WordPress.WP.AlternativeFunctions.json_encode_json_encode -- pure PHP (spec §4.4).
+        return json_encode($value, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_THROW_ON_ERROR);
+    }
+}
diff --git a/src/Integrations/Divi/BlockTree/MalformedMarkup.php b/src/Integrations/Divi/BlockTree/MalformedMarkup.php
new file mode 100644
index 0000000..f15cc1b
--- /dev/null
+++ b/src/Integrations/Divi/BlockTree/MalformedMarkup.php
@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\BlockTree;
+
+use RuntimeException;
+
+/**
+ * post_content is no balanced block markup (closer without opener, unclosed block, PCRE
+ * failure). The Divi tools then refuse to read or write the entry – nothing is guessed.
+ */
+final class MalformedMarkup extends RuntimeException
+{
+}
diff --git a/src/Integrations/Divi/BlockTree/Parser.php b/src/Integrations/Divi/BlockTree/Parser.php
new file mode 100644
index 0000000..afb4d25
--- /dev/null
+++ b/src/Integrations/Divi/BlockTree/Parser.php
@@ -0,0 +1,89 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\BlockTree;
+
+/**
+ * Parses block markup into a Document without WordPress (spec §4.4, §5.2). Uses the
+ * block-delimiter pattern of WP_Block_Parser, but records the exact bytes of every
+ * delimiter and of all text between them, so Serializer::document() reproduces the input
+ * byte for byte. Unbalanced markup is refused (MalformedMarkup), never repaired.
+ */
+final class Parser
+{
+    /** WP_Block_Parser::next_token() (WordPress 7.0). */
+    private const TOKEN = '/<!--\s+(?P<closer>\/)?wp:(?P<namespace>[a-z][a-z0-9_-]*\/)?(?P<name>[a-z][a-z0-9_-]*)\s+'
+        . '(?P<attrs>{(?:(?:[^}]+|}+(?=})|(?!}\s+\/?-->).)*+)?}\s+)?(?P<void>\/)?-->/s';
+
+    /** @throws MalformedMarkup */
+    public function parse(string $content): Document
+    {
+        $document = new Document();
+        /** @var list<Block> $stack */
+        $stack = [];
+        $offset = 0;
+        $length = strlen($content);
+
+        while ($offset < $length) {
+            $found = preg_match(self::TOKEN, $content, $match, PREG_OFFSET_CAPTURE, $offset);
+            if ($found === false) {
+                throw new MalformedMarkup('Block delimiters could not be scanned (PCRE error).');
+            }
+            if ($found === 0) {
+                break;
+            }
+
+            [$token, $start] = $match[0];
+            $container = $stack === [] ? $document : $stack[count($stack) - 1];
+            if ($start > $offset) {
+                $container->append(substr($content, $offset, $start - $offset));
+            }
+
+            $name = self::name($match);
+            if (self::captured($match, 'closer')) {
+                $open = array_pop($stack);
+                if ($open === null || $open->name() !== $name) {
+                    throw new MalformedMarkup(sprintf('Closer of %s at byte %d has no opener.', $name, $start));
+                }
+                $open->closeWith($token);
+            } else {
+                $json = self::captured($match, 'attrs') ? $match['attrs'][0] : '';
+                $attrs = $json === '' ? [] : Json::decodeObject($json);
+                $void = self::captured($match, 'void');
+                $opaque = $attrs === null || $name === 'divi/global-layout' || array_key_exists('globalModule', $attrs);
+                $block = Block::parsed($name, $attrs ?? [], $token, $void, $opaque);
+                $container->append($block);
+                if (! $void) {
+                    $stack[] = $block;
+                }
+            }
+
+            $offset = $start + strlen($token);
+        }
+
+        if ($offset < $length) {
+            ($stack === [] ? $document : $stack[count($stack) - 1])->append(substr($content, $offset));
+        }
+
+        if ($stack !== []) {
+            throw new MalformedMarkup(sprintf('Block %s is never closed.', $stack[count($stack) - 1]->name()));
+        }
+
+        return $document;
+    }
+
+    /** @param array<int|string, array{0: string, 1: int}> $match */
+    private static function name(array $match): string
+    {
+        $namespace = self::captured($match, 'namespace') ? $match['namespace'][0] : 'core/';
+
+        return $namespace . $match['name'][0];
+    }
+
+    /** @param array<int|string, array{0: string, 1: int}> $match */
+    private static function captured(array $match, string $group): bool
+    {
+        return isset($match[$group]) && $match[$group][1] !== -1 && $match[$group][0] !== '';
+    }
+}
diff --git a/src/Integrations/Divi/BlockTree/Serializer.php b/src/Integrations/Divi/BlockTree/Serializer.php
new file mode 100644
index 0000000..b298530
--- /dev/null
+++ b/src/Integrations/Divi/BlockTree/Serializer.php
@@ -0,0 +1,73 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\BlockTree;
+
+/**
+ * Turns a Document back into block markup. Unchanged blocks reuse their original
+ * delimiters; changed or new blocks get delimiters generated exactly like WordPress'
+ * get_comment_delimited_block_content() / serialize_block_attributes() do, which also
+ * yields the escaping Divi expects inside $variable(…)$ payloads (" → ").
+ */
+final class Serializer
+{
+    /** serialize_block_attributes() replacements (WordPress 7.0). */
+    private const ESCAPES = [
+        '\\\\' => '\\u005c',
+        '--' => '\\u002d\\u002d',
+        '<' => '\\u003c',
+        '>' => '\\u003e',
+        '&' => '\\u0026',
+        '\\"' => '\\u0022',
+    ];
+
+    public static function document(Document $document): string
+    {
+        return self::parts($document->parts());
+    }
+
+    public static function block(Block $block): string
+    {
+        $open = $block->rawOpen() ?? self::opener($block);
+        if ($block->isVoid()) {
+            return $open;
+        }
+
+        return $open . self::parts($block->parts()) . ($block->rawClose() ?? self::closer($block));
+    }
+
+    /** @param array<string, mixed> $attrs */
+    public static function attributes(array $attrs): string
+    {
+        return strtr(Json::encode($attrs), self::ESCAPES);
+    }
+
+    private static function opener(Block $block): string
+    {
+        $attrs = $block->attrs() === [] ? '' : self::attributes($block->attrs()) . ' ';
+
+        return '<!-- wp:' . self::serializedName($block->name()) . ' ' . $attrs . ($block->isVoid() ? '/-->' : '-->');
+    }
+
+    private static function closer(Block $block): string
+    {
+        return '<!-- /wp:' . self::serializedName($block->name()) . ' -->';
+    }
+
+    private static function serializedName(string $name): string
+    {
+        return str_starts_with($name, 'core/') ? substr($name, 5) : $name;
+    }
+
+    /** @param list<string|Block> $parts */
+    private static function parts(array $parts): string
+    {
+        $out = '';
+        foreach ($parts as $part) {
+            $out .= $part instanceof Block ? self::block($part) : $part;
+        }
+
+        return $out;
+    }
+}
diff --git a/tests/Fixtures/divi/converted-features.html b/tests/Fixtures/divi/converted-features.html
new file mode 100644
index 0000000..ea4836a
--- /dev/null
+++ b/tests/Fixtures/divi/converted-features.html
@@ -0,0 +1 @@
+<!-- wp:divi/placeholder --><!-- wp:divi/section {"module":{"meta":{"adminLabel":{"desktop":{"value":"Details"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/row {"module":{"advanced":{"columnStructure":{"desktop":{"value":"2_3,1_3"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"2_3"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/tabs {"builderVersion":"4.27.4"} --><!-- wp:divi/tab {"title":{"innerContent":{"desktop":{"value":"Ablauf"}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eErst reden, dann bauen.\u003c/p\u003e"}}}} --><!-- /wp:divi/tab --><!-- wp:divi/tab {"title":{"innerContent":{"desktop":{"value":"Preise"}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eAb 99 €.\u003c/p\u003e"}}}} --><!-- /wp:divi/tab --><!-- /wp:divi/tabs --><!-- wp:divi/toggle {"title":{"innerContent":{"desktop":{"value":"Garantie"}}},"module":{"advanced":{"open":{"desktop":{"value":"off"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003e5 Jahre.\u003c/p\u003e"}}}} --><!-- /wp:divi/toggle --><!-- wp:divi/slider {"builderVersion":"4.27.4","module":{"advanced":{"text":{"text":{"desktop":{"value":{"orientation":"center"}}}}}}} --><!-- wp:divi/slide {"title":{"innerContent":{"desktop":{"value":"Neu"}}},"button":{"innerContent":{"desktop":{"value":{"text":"Mehr","linkUrl":"/neu"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eUnsere neue Halle.\u003c/p\u003e"}}},"module":{"advanced":{"text":{"text":{"desktop":{"value":{"orientation":"center"}}}}}}} --><!-- /wp:divi/slide --><!-- /wp:divi/slider --><!-- wp:divi/gallery {"image":{"advanced":{"galleryIds":{"desktop":{"value":"12,33"}}}},"builderVersion":"5.0.0-public-alpha.18.2","galleryGrid":{"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}}} --><!-- /wp:divi/gallery --><!-- wp:divi/code {"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cdiv class=\u0022hinweis\u0022\u003eCode\u003c/div\u003e"}}}} --><!-- /wp:divi/code --><!-- /wp:divi/column --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"1_3"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/team-member {"name":{"innerContent":{"desktop":{"value":"Max Meister"}}},"position":{"innerContent":{"desktop":{"value":"Inhaber"}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eMeister seit 2001.\u003c/p\u003e"}}},"module":{"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}}} --><!-- /wp:divi/team-member --><!-- wp:divi/number-counter {"title":{"innerContent":{"desktop":{"value":"Projekte"}}},"number":{"innerContent":{"desktop":{"value":"480"}},"advanced":{"enablePercentSign":{"desktop":{"value":"off"}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/number-counter --><!-- wp:divi/divider {"divider":{"advanced":{"line":{"desktop":{"value":{"show":"on"}}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/divider --><!-- wp:divi/social-media-follow {"builderVersion":"5.0.0-public-alpha.18.2","module":{"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}}} --><!-- wp:divi/social-media-follow-network {"socialNetwork":{"innerContent":{"desktop":{"value":{"title":"facebook","link":"https://facebook.com/example","label":"facebook"}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/social-media-follow-network --><!-- /wp:divi/social-media-follow --><!-- wp:divi/map {"map":{"innerContent":{"desktop":{"value":{"address":"Domkloster 4, 50667 Köln","lat":50.9413,"lng":6.9583}}}},"builderVersion":"4.27.4"} --><!-- wp:divi/map-pin {"title":{"innerContent":{"desktop":{"value":"Büro"}}},"pin":{"innerContent":{"desktop":{"value":{"address":"Domkloster 4, 50667 Köln","lat":50.9413,"lng":6.9583}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/map-pin --><!-- /wp:divi/map --><!-- wp:divi/video {"video":{"innerContent":{"desktop":{"value":{"src":"https://www.youtube.com/watch?v=dQw4w9WgXcQ"}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/video --><!-- /wp:divi/column --><!-- /wp:divi/row --><!-- /wp:divi/section --><!-- /wp:divi/placeholder -->
\ No newline at end of file
diff --git a/tests/Fixtures/divi/converted-landing.html b/tests/Fixtures/divi/converted-landing.html
new file mode 100644
index 0000000..3bac6f6
--- /dev/null
+++ b/tests/Fixtures/divi/converted-landing.html
@@ -0,0 +1 @@
+<!-- wp:divi/placeholder --><!-- wp:divi/section {"module":{"meta":{"adminLabel":{"desktop":{"value":"Hero"}}},"decoration":{"background":{"desktop":{"value":{"color":"#0b3d59"}}},"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/row {"module":{"advanced":{"columnStructure":{"desktop":{"value":"1_2,1_2"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"1_2"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/heading {"title":{"innerContent":{"desktop":{"value":"Handwerk mit Herz"}},"decoration":{"font":{"font":{"desktop":{"value":{"headingLevel":"h1"}}}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/heading --><!-- wp:divi/text {"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eSeit 1987 in \u003cstrong\u003eKöln\u003c/strong\u003e – \u0022fair\u0022 \u0026amp; pünktlich.\u003c/p\u003e"}}}} --><!-- /wp:divi/text --><!-- wp:divi/button {"button":{"innerContent":{"desktop":{"value":{"text":"Termin buchen","linkUrl":"/kontakt"}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/button --><!-- /wp:divi/column --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"1_2"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/image {"image":{"innerContent":{"desktop":{"value":{"src":"https://example.test/wp-content/uploads/2026/09/werkstatt.jpg","alt":"Werkstatt","titleText":"Werkstatt"}}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/image --><!-- /wp:divi/column --><!-- /wp:divi/row --><!-- /wp:divi/section --><!-- wp:divi/section {"module":{"meta":{"adminLabel":{"desktop":{"value":"Leistungen"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/row {"module":{"advanced":{"columnStructure":{"desktop":{"value":"1_3,1_3,1_3"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"1_3"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/blurb {"title":{"innerContent":{"desktop":{"value":{"text":"Beratung"}}}},"imageIcon":{"innerContent":{"desktop":{"value":{"useIcon":"on","icon":{"unicode":"\u0026#xe08b;","type":"divi","weight":"400"}}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003ePersönlich vor Ort.\u003c/p\u003e"}}}} --><!-- /wp:divi/blurb --><!-- /wp:divi/column --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"1_3"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/blurb {"title":{"innerContent":{"desktop":{"value":{"text":"Planung"}}}},"imageIcon":{"innerContent":{"desktop":{"value":{"src":"https://example.test/wp-content/uploads/2026/09/plan.png","alt":"Plan"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eMit 3D-Ansicht.\u003c/p\u003e"}}}} --><!-- /wp:divi/blurb --><!-- /wp:divi/column --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"1_3"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/blurb {"title":{"innerContent":{"desktop":{"value":{"text":"Umsetzung"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eTermingerecht.\u003c/p\u003e"}}}} --><!-- /wp:divi/blurb --><!-- /wp:divi/column --><!-- /wp:divi/row --><!-- wp:divi/row {"builderVersion":"5.0.0-public-alpha.18.2","module":{"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}}} --><!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"4_4"}}},"decoration":{"layout":{"desktop":{"value":{"display":"block"}}}}},"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/cta {"title":{"innerContent":{"desktop":{"value":"Bereit?"}}},"button":{"innerContent":{"desktop":{"value":{"text":"Anfragen","linkUrl":"/kontakt"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eWir melden uns binnen 24 Stunden.\u003c/p\u003e"}}}} --><!-- /wp:divi/cta --><!-- wp:divi/testimonial {"author":{"innerContent":{"desktop":{"value":"Anna B."}}},"jobTitle":{"innerContent":{"desktop":{"value":"Bauherrin"}}},"company":{"innerContent":{"desktop":{"value":{"text":"Privat"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eTop Arbeit!\u003c/p\u003e"}}}} --><!-- /wp:divi/testimonial --><!-- wp:divi/accordion {"builderVersion":"5.0.0-public-alpha.18.2"} --><!-- wp:divi/accordion-item {"title":{"innerContent":{"desktop":{"value":"Was kostet das?"}}},"module":{"advanced":{"open":{"desktop":{"value":"on"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003eKommt drauf an.\u003c/p\u003e"}}}} --><!-- /wp:divi/accordion-item --><!-- wp:divi/accordion-item {"title":{"innerContent":{"desktop":{"value":"Wie schnell?"}}},"module":{"advanced":{"open":{"desktop":{"value":"off"}}}},"builderVersion":"4.27.4","content":{"innerContent":{"desktop":{"value":"\u003cp\u003e2 Wochen.\u003c/p\u003e"}}}} --><!-- /wp:divi/accordion-item --><!-- /wp:divi/accordion --><!-- wp:divi/contact-form {"email":{"advanced":{"receiver":{"desktop":{"value":"info@example.test"}}}},"title":{"innerContent":{"desktop":{"value":"Kontakt"}}},"builderVersion":"4.27.4"} --><!-- wp:divi/contact-field {"fieldItem":{"advanced":{"id":{"desktop":{"value":"Name"}}},"innerContent":{"desktop":{"value":"Name"}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/contact-field --><!-- wp:divi/contact-field {"fieldItem":{"advanced":{"id":{"desktop":{"value":"Email"}},"type":{"desktop":{"value":"email"}}},"innerContent":{"desktop":{"value":"E-Mail"}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/contact-field --><!-- wp:divi/contact-field {"fieldItem":{"advanced":{"id":{"desktop":{"value":"Message"}},"type":{"desktop":{"value":"text"}},"fullwidth":{"desktop":{"value":"on"}}},"innerContent":{"desktop":{"value":"Nachricht"}}},"builderVersion":"4.27.4"} --><!-- /wp:divi/contact-field --><!-- /wp:divi/contact-form --><!-- /wp:divi/column --><!-- /wp:divi/row --><!-- /wp:divi/section --><!-- /wp:divi/placeholder -->
\ No newline at end of file
diff --git a/tests/Fixtures/divi/divi4-shortcodes.html b/tests/Fixtures/divi/divi4-shortcodes.html
new file mode 100644
index 0000000..5c80067
--- /dev/null
+++ b/tests/Fixtures/divi/divi4-shortcodes.html
@@ -0,0 +1 @@
+[et_pb_section fb_built="1" _builder_version="4.27.4"][et_pb_row _builder_version="4.27.4"][et_pb_column type="4_4"][et_pb_text]<p>Divi 4</p>[/et_pb_text][/et_pb_column][/et_pb_row][/et_pb_section]
\ No newline at end of file
diff --git a/tests/Fixtures/divi/source/features.shortcode b/tests/Fixtures/divi/source/features.shortcode
new file mode 100644
index 0000000..b3d6379
--- /dev/null
+++ b/tests/Fixtures/divi/source/features.shortcode
@@ -0,0 +1 @@
+[et_pb_section fb_built="1" admin_label="Details" _builder_version="4.27.4"][et_pb_row column_structure="2_3,1_3" _builder_version="4.27.4"][et_pb_column type="2_3" _builder_version="4.27.4"][et_pb_tabs _builder_version="4.27.4"][et_pb_tab title="Ablauf" _builder_version="4.27.4"]<p>Erst reden, dann bauen.</p>[/et_pb_tab][et_pb_tab title="Preise" _builder_version="4.27.4"]<p>Ab 99 €.</p>[/et_pb_tab][/et_pb_tabs][et_pb_toggle title="Garantie" open="off" _builder_version="4.27.4"]<p>5 Jahre.</p>[/et_pb_toggle][et_pb_slider _builder_version="4.27.4"][et_pb_slide heading="Neu" button_text="Mehr" button_link="/neu" _builder_version="4.27.4"]<p>Unsere neue Halle.</p>[/et_pb_slide][/et_pb_slider][et_pb_gallery gallery_ids="12,33" _builder_version="4.27.4"][/et_pb_gallery][et_pb_code _builder_version="4.27.4"]<div class="hinweis">Code</div>[/et_pb_code][/et_pb_column][et_pb_column type="1_3" _builder_version="4.27.4"][et_pb_team_member name="Max Meister" position="Inhaber" _builder_version="4.27.4"]<p>Meister seit 2001.</p>[/et_pb_team_member][et_pb_number_counter title="Projekte" number="480" percent_sign="off" _builder_version="4.27.4"][/et_pb_number_counter][et_pb_divider show_divider="on" _builder_version="4.27.4"][/et_pb_divider][et_pb_social_media_follow _builder_version="4.27.4"][et_pb_social_media_follow_network social_network="facebook" url="https://facebook.com/example" _builder_version="4.27.4"]facebook[/et_pb_social_media_follow_network][/et_pb_social_media_follow][et_pb_map address="Domkloster 4, 50667 Köln" address_lat="50.9413" address_lng="6.9583" _builder_version="4.27.4"][et_pb_map_pin title="Büro" pin_address="Domkloster 4, 50667 Köln" pin_address_lat="50.9413" pin_address_lng="6.9583" _builder_version="4.27.4"][/et_pb_map_pin][/et_pb_map][et_pb_video src="https://www.youtube.com/watch?v=dQw4w9WgXcQ" _builder_version="4.27.4"][/et_pb_video][/et_pb_column][/et_pb_row][/et_pb_section]
\ No newline at end of file
diff --git a/tests/Fixtures/divi/source/landing.shortcode b/tests/Fixtures/divi/source/landing.shortcode
new file mode 100644
index 0000000..92b999d
--- /dev/null
+++ b/tests/Fixtures/divi/source/landing.shortcode
@@ -0,0 +1 @@
+[et_pb_section fb_built="1" admin_label="Hero" _builder_version="4.27.4" background_color="#0b3d59"][et_pb_row column_structure="1_2,1_2" _builder_version="4.27.4"][et_pb_column type="1_2" _builder_version="4.27.4"][et_pb_heading title="Handwerk mit Herz" title_level="h1" _builder_version="4.27.4"][/et_pb_heading][et_pb_text _builder_version="4.27.4"]<p>Seit 1987 in <strong>Köln</strong> – "fair" &amp; pünktlich.</p>[/et_pb_text][et_pb_button button_text="Termin buchen" button_url="/kontakt" _builder_version="4.27.4"][/et_pb_button][/et_pb_column][et_pb_column type="1_2" _builder_version="4.27.4"][et_pb_image src="https://example.test/wp-content/uploads/2026/09/werkstatt.jpg" alt="Werkstatt" title_text="Werkstatt" _builder_version="4.27.4"][/et_pb_image][/et_pb_column][/et_pb_row][/et_pb_section][et_pb_section fb_built="1" admin_label="Leistungen" _builder_version="4.27.4"][et_pb_row column_structure="1_3,1_3,1_3" _builder_version="4.27.4"][et_pb_column type="1_3" _builder_version="4.27.4"][et_pb_blurb title="Beratung" use_icon="on" font_icon="&#xe08b;||divi||400" _builder_version="4.27.4"]<p>Persönlich vor Ort.</p>[/et_pb_blurb][/et_pb_column][et_pb_column type="1_3" _builder_version="4.27.4"][et_pb_blurb title="Planung" image="https://example.test/wp-content/uploads/2026/09/plan.png" alt="Plan" _builder_version="4.27.4"]<p>Mit 3D-Ansicht.</p>[/et_pb_blurb][/et_pb_column][et_pb_column type="1_3" _builder_version="4.27.4"][et_pb_blurb title="Umsetzung" _builder_version="4.27.4"]<p>Termingerecht.</p>[/et_pb_blurb][/et_pb_column][/et_pb_row][et_pb_row _builder_version="4.27.4"][et_pb_column type="4_4" _builder_version="4.27.4"][et_pb_cta title="Bereit?" button_text="Anfragen" button_url="/kontakt" _builder_version="4.27.4"]<p>Wir melden uns binnen 24 Stunden.</p>[/et_pb_cta][et_pb_testimonial author="Anna B." job_title="Bauherrin" company_name="Privat" _builder_version="4.27.4"]<p>Top Arbeit!</p>[/et_pb_testimonial][et_pb_accordion _builder_version="4.27.4"][et_pb_accordion_item title="Was kostet das?" open="on" _builder_version="4.27.4"]<p>Kommt drauf an.</p>[/et_pb_accordion_item][et_pb_accordion_item title="Wie schnell?" open="off" _builder_version="4.27.4"]<p>2 Wochen.</p>[/et_pb_accordion_item][/et_pb_accordion][et_pb_contact_form email="info@example.test" title="Kontakt" _builder_version="4.27.4"][et_pb_contact_field field_id="Name" field_title="Name" _builder_version="4.27.4"][/et_pb_contact_field][et_pb_contact_field field_id="Email" field_title="E-Mail" field_type="email" _builder_version="4.27.4"][/et_pb_contact_field][et_pb_contact_field field_id="Message" field_title="Nachricht" field_type="text" fullwidth_field="on" _builder_version="4.27.4"][/et_pb_contact_field][/et_pb_contact_form][/et_pb_column][/et_pb_row][/et_pb_section]
\ No newline at end of file
diff --git a/tests/Fixtures/divi/synthetic-basic.html b/tests/Fixtures/divi/synthetic-basic.html
new file mode 100644
index 0000000..623ea83
--- /dev/null
+++ b/tests/Fixtures/divi/synthetic-basic.html
@@ -0,0 +1 @@
+<!-- wp:divi/placeholder --><!-- wp:divi/section {"module":{"meta":{"adminLabel":{"desktop":{"value":"Hero"}}},"decoration":{"background":{"desktop":{"value":{"color":"$variable({\u0022type\u0022:\u0022color\u0022,\u0022value\u0022:{\u0022name\u0022:\u0022gcid-primary-color\u0022,\u0022settings\u0022:{}}})$"}}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/row {"module":{"meta":{"adminLabel":{"desktop":{"value":"Hero – Zeile"}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/column {"module":{"decoration":{"sizing":{"desktop":{"value":{"flexType":"8_24"}}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/image {"image":{"innerContent":{"desktop":{"value":{"src":"https://kunde.test/wp-content/uploads/2026/09/team.jpg","id":"33","alt":"Unser Team vor dem Büro"}}}},"module":{"meta":{"adminLabel":{"desktop":{"value":"Hero – Bild"}}}},"builderVersion":"5.2.1"} /--><!-- /wp:divi/column --><!-- wp:divi/column {"module":{"decoration":{"sizing":{"desktop":{"value":{"flexType":"16_24"}}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/heading {"title":{"innerContent":{"desktop":{"value":"Willkommen bei Müller \u0026 Söhne"}},"decoration":{"font":{"font":{"desktop":{"value":{"headingLevel":"h1","color":"#1a1a1a"}},"phone":{"value":{"size":"28px"}}}}}},"modulePreset":["a1b2c3d4-e5f6-4a7b-8c9d-0e1f2a3b4c5d"],"builderVersion":"5.2.1"} --><!-- /wp:divi/heading --><!-- wp:divi/text {"content":{"innerContent":{"desktop":{"value":"\u003cp\u003eSeit 1987 \u003cstrong\u003ezuverlässig\u003c/strong\u003e – \u003ca href=\u0022/kontakt\u0022\u003ejetzt anfragen\u003c/a\u003e.\u003c/p\u003e\u003c!\u002d\u002d more \u002d\u002d\u003e"}}},"builderVersion":"5.2.1"} --><!-- /wp:divi/text --><!-- wp:divi/button {"button":{"innerContent":{"desktop":{"value":{"text":"Termin buchen","linkUrl":"/kontakt","linkTarget":"off"}}}},"module":{"meta":{"adminLabel":{"desktop":{"value":"Hero – Button"}}}},"builderVersion":"5.2.1"} --><!-- /wp:divi/button --><!-- /wp:divi/column --><!-- /wp:divi/row --><!-- /wp:divi/section --><!-- wp:divi/section {"module":{"meta":{"adminLabel":{"desktop":{"value":"Leistungen"}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/row {"builderVersion":"5.2.1"} --><!-- wp:divi/column {"module":{"decoration":{"sizing":{"desktop":{"value":{"flexType":"12_24"}}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/blurb {"title":{"innerContent":{"desktop":{"value":{"text":"Beratung","url":""}}},"decoration":{"font":{"font":{"desktop":{"value":{"headingLevel":"h3"}}}}}},"content":{"innerContent":{"desktop":{"value":"\u003cp\u003ePersönlich und \u0022ehrlich\u0022.\u003c/p\u003e"}}},"imageIcon":{"innerContent":{"desktop":{"value":{"useIcon":"on","icon":{"unicode":"\u0026#xe08b;","type":"divi","weight":"400"}}}}},"builderVersion":"5.2.1"} --><!-- /wp:divi/blurb --><!-- /wp:divi/column --><!-- wp:divi/column {"module":{"decoration":{"sizing":{"desktop":{"value":{"flexType":"12_24"}}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/accordion {"builderVersion":"5.2.1"} --><!-- wp:divi/accordion-item {"title":{"innerContent":{"desktop":{"value":"Was kostet das?"}}},"content":{"innerContent":{"desktop":{"value":"\u003cp\u003eKommt drauf an.\u003c/p\u003e"}}},"module":{"advanced":{"open":{"desktop":{"value":"on"}}}},"builderVersion":"5.2.1"} --><!-- /wp:divi/accordion-item --><!-- wp:divi/accordion-item {"title":{"innerContent":{"desktop":{"value":"Wie schnell?"}}},"content":{"innerContent":{"desktop":{"value":"\u003cp\u003eIn 2 Wochen.\u003c/p\u003e"}}},"builderVersion":"5.2.1"} --><!-- /wp:divi/accordion-item --><!-- /wp:divi/accordion --><!-- /wp:divi/column --><!-- /wp:divi/row --><!-- /wp:divi/section --><!-- /wp:divi/placeholder -->
\ No newline at end of file
diff --git a/tests/Fixtures/divi/synthetic-mixed.html b/tests/Fixtures/divi/synthetic-mixed.html
new file mode 100644
index 0000000..18341e1
--- /dev/null
+++ b/tests/Fixtures/divi/synthetic-mixed.html
@@ -0,0 +1,12 @@
+<!-- wp:paragraph -->
+<p>Einleitung aus dem Block-Editor mit <a href="https://example.test" target="_blank">Link</a>.</p>
+<!-- /wp:paragraph -->
+
+<!-- wp:divi/placeholder -->
+<!-- wp:divi/section {"module":{"advanced":{"type":{"desktop":{"value":"specialty"}}}},"builderVersion":"5.2.1"} -->
+<!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"1_3"}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/text {"content":{"innerContent":{"desktop":{"value":"Seitenleiste"}}},"builderVersion":"5.2.1"} /--><!-- /wp:divi/column -->
+<!-- wp:divi/column {"module":{"advanced":{"type":{"desktop":{"value":"2_3"}},"specialtyColumns":{"desktop":{"value":"2"}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/row-inner {"module":{"advanced":{"columnStructure":{"desktop":{"value":"1_2,1_2"}}}},"builderVersion":"5.2.1"} --><!-- wp:divi/column-inner {"builderVersion":"5.2.1"} --><!-- wp:divi/code {"content":{"innerContent":{"desktop":{"value":"\u003cscript\u003econsole.log(\u0022a\u002d\u002db\u0022)\u003c/script\u003e"}}},"builderVersion":"5.2.1"} /--><!-- /wp:divi/column-inner --><!-- wp:divi/column-inner {"builderVersion":"5.2.1"} --><!-- /wp:divi/column-inner --><!-- /wp:divi/row-inner --><!-- /wp:divi/column -->
+<!-- /wp:divi/section -->
+<!-- wp:divi/section {"builderVersion":"5.2.1","module":{"decoration":{"spacing":{"desktop":{"value":{}}},"background":{"desktop":{"value":[]}}}},"localAttrs":{"0":"x","1":"y"}} --><!-- wp:divi/global-layout {"globalModule":"812","builderVersion":"5.2.1"} /--><!-- wp:divi/row {"globalModule":"913","module":{"meta":{"adminLabel":{"desktop":{"value":"Globale Zeile"}}}}} --><!-- wp:divi/column {"builderVersion":"5.2.1"} --><!-- wp:divi/text {"content":{"innerContent":{"desktop":{"value":"lokal"}}}} /--><!-- /wp:divi/column --><!-- /wp:divi/row --><!-- wp:divi/global-layout {"globalModule":"914","localAttrs":{"title":"x"}} --><!-- wp:divi/text {"content":{"innerContent":{"desktop":{"value":"Kind"}}}} /--><!-- /wp:divi/global-layout --><!-- /wp:divi/section -->
+<!-- /wp:divi/placeholder -->
+Freier Text am Ende [et_pb_legacy]
diff --git a/tests/Integration/divi-convert-fixture.php b/tests/Integration/divi-convert-fixture.php
new file mode 100644
index 0000000..02d8565
--- /dev/null
+++ b/tests/Integration/divi-convert-fixture.php
@@ -0,0 +1,35 @@
+<?php
+/**
+ * Generates a Divi 5 fixture from a Divi 4 shortcode file with Divi's own server-side
+ * conversion (the same code the Divi 5 migrator uses) and writes it into tests/Fixtures/divi/.
+ * Usage (inside DDEV, from the WordPress root):
+ *   wp eval-file wp-content/plugins/WP-LIT-MCP/tests/Integration/divi-convert-fixture.php <source.shortcode> <target.html>
+ * Paths are relative to the plugin's tests/Fixtures/divi directory.
+ */
+
+use ET\Builder\Packages\Conversion\Conversion;
+
+$args = $args ?? [];
+if (count($args) !== 2) {
+    WP_CLI::error('Usage: divi-convert-fixture.php <source.shortcode> <target.html>');
+}
+if (! class_exists(Conversion::class)) {
+    WP_CLI::error('Divi 5 is not active.');
+}
+
+$dir = dirname(__DIR__) . '/Fixtures/divi/';
+$source = file_get_contents($dir . $args[0]);
+if ($source === false) {
+    WP_CLI::error('Cannot read ' . $dir . $args[0]);
+}
+
+$converted = Conversion::maybeConvertContent(trim($source));
+if (! str_contains($converted, '<!-- wp:divi/section')) {
+    WP_CLI::error('Conversion produced no Divi 5 sections.');
+}
+
+$markup = '<!-- wp:divi/placeholder -->' . $converted . '<!-- /wp:divi/placeholder -->';
+if (file_put_contents($dir . $args[1], $markup) === false) {
+    WP_CLI::error('Cannot write ' . $dir . $args[1]);
+}
+WP_CLI::success(sprintf('%s: %d bytes', $args[1], strlen($markup)));
diff --git a/tests/Integration/divi-export-page.php b/tests/Integration/divi-export-page.php
new file mode 100644
index 0000000..acb8e98
--- /dev/null
+++ b/tests/Integration/divi-export-page.php
@@ -0,0 +1,45 @@
+<?php
+
+/**
+ * Exports the post_content of a page built in the Divi Visual Builder byte-exact into
+ * tests/Fixtures/divi/builder-<name>.html. Every file there is part of the parse → serialize
+ * round-trip test (tests/Unit/Integrations/Divi/BlockTree/ParserTest.php).
+ * Usage (DDEV, WordPress root):
+ *   wp eval-file wp-content/plugins/WP-LIT-MCP/tests/Integration/divi-export-page.php <post_id> <name>
+ * <name>: lowercase letters, digits and dashes, e.g. "startseite-mit-global".
+ * Only use pages without personal data – fixtures are committed.
+ * No `declare(strict_types=1);` – wp eval-file runs the file through eval().
+ */
+
+defined('WP_CLI') && WP_CLI || exit;
+
+$args = $args ?? [];
+$postId = (int) ($args[0] ?? 0);
+$name = (string) ($args[1] ?? '');
+if ($postId <= 0 || preg_match('/^[a-z0-9]+(-[a-z0-9]+)*$/', $name) !== 1) {
+    WP_CLI::error('Usage: divi-export-page.php <post_id> <name>');
+}
+
+$post = get_post($postId);
+if (! $post instanceof WP_Post) {
+    WP_CLI::error('No post ' . $postId);
+}
+
+$content = (string) $post->post_content;
+if (! str_contains($content, '<!-- wp:divi/')) {
+    WP_CLI::error('Post ' . $postId . ' has no Divi 5 content (open and save it in the Divi builder first).');
+}
+
+$file = dirname(__DIR__) . '/Fixtures/divi/builder-' . $name . '.html';
+if (file_put_contents($file, $content) === false) {
+    WP_CLI::error('Cannot write ' . $file);
+}
+
+WP_CLI::success(sprintf(
+    '%s: %d bytes, %d blocks, globalModule: %s, tree_rev %s. Now run composer test.',
+    basename($file),
+    strlen($content),
+    substr_count($content, '<!-- wp:'),
+    str_contains($content, 'globalModule') ? 'yes' : 'no',
+    substr(hash('sha256', $content), 0, 12)
+));
diff --git a/tests/Unit/Integrations/Divi/BlockTree/ParserTest.php b/tests/Unit/Integrations/Divi/BlockTree/ParserTest.php
new file mode 100644
index 0000000..a3904e4
--- /dev/null
+++ b/tests/Unit/Integrations/Divi/BlockTree/ParserTest.php
@@ -0,0 +1,138 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Tests\Unit\Integrations\Divi\BlockTree;
+
+use LIT\MCP\Integrations\Divi\BlockTree\Block;
+use LIT\MCP\Integrations\Divi\BlockTree\MalformedMarkup;
+use LIT\MCP\Integrations\Divi\BlockTree\Parser;
+use LIT\MCP\Integrations\Divi\BlockTree\Serializer;
+use PHPUnit\Framework\TestCase;
+use stdClass;
+
+final class ParserTest extends TestCase
+{
+    /** @return array<string, array{string}> Every fixture page, also with Windows line endings. */
+    public static function fixtures(): array
+    {
+        $cases = [];
+        foreach (glob(dirname(__DIR__, 4) . '/Fixtures/divi/*.html') ?: [] as $file) {
+            $content = (string) file_get_contents($file);
+            $cases[basename($file)] = [$content];
+            $cases[basename($file) . ' (CRLF)'] = [str_replace("\n", "\r\n", $content)];
+        }
+
+        return $cases;
+    }
+
+    /** @dataProvider fixtures */
+    public function testParseThenSerializeIsByteIdentical(string $content): void
+    {
+        self::assertSame($content, Serializer::document((new Parser())->parse($content)));
+    }
+
+    public function testFixturesArePresent(): void
+    {
+        $names = array_map('basename', glob(dirname(__DIR__, 4) . '/Fixtures/divi/*.html') ?: []);
+
+        self::assertContains('synthetic-basic.html', $names);
+        self::assertContains('synthetic-mixed.html', $names);
+        self::assertContains('converted-landing.html', $names);
+        self::assertContains('converted-features.html', $names);
+    }
+
+    public function testBuildsTheTree(): void
+    {
+        $document = (new Parser())->parse($this->fixture('synthetic-basic.html'));
+
+        $placeholder = $document->children()[0];
+        self::assertSame('divi/placeholder', $placeholder->name());
+        $sections = $placeholder->children();
+        self::assertCount(2, $sections);
+        self::assertSame('divi/section', $sections[0]->name());
+        self::assertFalse($sections[0]->isOpaque());
+        self::assertSame(
+            '$variable({"type":"color","value":{"name":"gcid-primary-color","settings":{}}})$',
+            $sections[0]->attrs()['module']['decoration']['background']['desktop']['value']['color']
+        );
+        $columns = $sections[0]->children()[0]->children();
+        self::assertSame(['divi/column', 'divi/column'], array_map(static fn (Block $b): string => $b->name(), $columns));
+        self::assertTrue($columns[0]->children()[0]->isVoid());
+        self::assertSame('image', $columns[0]->children()[0]->shortName());
+        self::assertSame(
+            'Willkommen bei Müller & Söhne',
+            $columns[1]->children()[0]->attrs()['title']['innerContent']['desktop']['value']
+        );
+    }
+
+    public function testKeepsTextBetweenBlocksAndNamesCoreBlocks(): void
+    {
+        $document = (new Parser())->parse("<!-- wp:paragraph -->\n<p>x</p>\n<!-- /wp:paragraph -->\n\ntext");
+
+        self::assertSame('core/paragraph', $document->children()[0]->name());
+        self::assertSame(["\n<p>x</p>\n"], $document->children()[0]->parts());
+        self::assertSame("\n\ntext", $document->parts()[1]);
+    }
+
+    public function testMarksGlobalAndUndecodableBlocksOpaque(): void
+    {
+        $document = (new Parser())->parse($this->fixture('synthetic-mixed.html'));
+        $placeholder = $document->children()[1];
+        $second = $placeholder->children()[1];
+        [$globalLayout, $globalRow, $globalWithChild] = $second->children();
+
+        self::assertTrue($globalLayout->isOpaque());
+        self::assertTrue($globalLayout->isGlobal());
+        self::assertTrue($globalRow->isOpaque());
+        self::assertTrue($globalRow->isGlobal());
+        self::assertTrue($globalWithChild->isOpaque());
+        self::assertFalse($second->isOpaque());
+
+        $broken = (new Parser())->parse('<!-- wp:divi/text {"a":} /-->');
+        self::assertTrue($broken->children()[0]->isOpaque());
+        self::assertSame([], $broken->children()[0]->attrs());
+    }
+
+    public function testKeepsEmptyAndListLikeObjectsAsObjects(): void
+    {
+        $document = (new Parser())->parse($this->fixture('synthetic-mixed.html'));
+        $attrs = $document->children()[1]->children()[1]->attrs();
+
+        self::assertInstanceOf(stdClass::class, $attrs['module']['decoration']['spacing']['desktop']['value']);
+        self::assertSame([], $attrs['module']['decoration']['background']['desktop']['value']);
+        self::assertInstanceOf(stdClass::class, $attrs['localAttrs']);
+    }
+
+    public function testDivi4ShortcodesAreOneTextPart(): void
+    {
+        $content = $this->fixture('divi4-shortcodes.html');
+        $document = (new Parser())->parse($content);
+
+        self::assertSame([], $document->children());
+        self::assertSame([$content], $document->parts());
+    }
+
+    /** @return array<string, array{string}> */
+    public static function malformed(): array
+    {
+        return [
+            'closer without opener' => ['<!-- /wp:divi/section -->'],
+            'unclosed block' => ['<!-- wp:divi/section --><!-- wp:divi/row --><!-- /wp:divi/row -->'],
+            'crossed blocks' => ['<!-- wp:divi/row --><!-- wp:divi/column --><!-- /wp:divi/row --><!-- /wp:divi/column -->'],
+        ];
+    }
+
+    /** @dataProvider malformed */
+    public function testRefusesUnbalancedMarkup(string $content): void
+    {
+        $this->expectException(MalformedMarkup::class);
+
+        (new Parser())->parse($content);
+    }
+
+    private function fixture(string $name): string
+    {
+        return (string) file_get_contents(dirname(__DIR__, 4) . '/Fixtures/divi/' . $name);
+    }
+}
diff --git a/tests/Unit/Integrations/Divi/BlockTree/SerializerTest.php b/tests/Unit/Integrations/Divi/BlockTree/SerializerTest.php
new file mode 100644
index 0000000..3cee656
--- /dev/null
+++ b/tests/Unit/Integrations/Divi/BlockTree/SerializerTest.php
@@ -0,0 +1,103 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Tests\Unit\Integrations\Divi\BlockTree;
+
+use LIT\MCP\Integrations\Divi\BlockTree\Block;
+use LIT\MCP\Integrations\Divi\BlockTree\Document;
+use LIT\MCP\Integrations\Divi\BlockTree\Parser;
+use LIT\MCP\Integrations\Divi\BlockTree\Serializer;
+use PHPUnit\Framework\TestCase;
+use stdClass;
+
+final class SerializerTest extends TestCase
+{
+    public function testEscapesAttributesLikeWordPress(): void
+    {
+        $variable = '$variable({"type":"color","value":{"name":"gcid-primary-color","settings":{}}})$';
+
+        self::assertSame(
+            '{"c":"$variable({\u0022type\u0022:\u0022color\u0022,\u0022value\u0022:{\u0022name\u0022:'
+                . '\u0022gcid-primary-color\u0022,\u0022settings\u0022:{}}})$"}',
+            Serializer::attributes(['c' => $variable])
+        );
+        self::assertSame(
+            '{"t":"\u003cp\u003eA \u0026 B\u003c/p\u003e \u002d\u002d \u005c/ ä","e":{},"l":[]}',
+            Serializer::attributes(['t' => '<p>A & B</p> -- \\/ ä', 'e' => new stdClass(), 'l' => []])
+        );
+    }
+
+    public function testRegeneratesOnlyTheChangedOpener(): void
+    {
+        $content = '<!-- wp:divi/section {"b":1}  --><!-- wp:divi/text   {"x":"y"} /--><!-- /wp:divi/section -->';
+        $document = (new Parser())->parse($content);
+        $text = $document->children()[0]->children()[0];
+
+        $text->setAttrs(['x' => 'z']);
+
+        self::assertSame(
+            '<!-- wp:divi/section {"b":1}  --><!-- wp:divi/text {"x":"z"} /--><!-- /wp:divi/section -->',
+            Serializer::document($document)
+        );
+    }
+
+    public function testNewBlocksAreWrittenAsPairs(): void
+    {
+        $block = Block::create('divi/row', ['builderVersion' => '5.2.1'], [Block::create('divi/column')]);
+
+        self::assertSame(
+            '<!-- wp:divi/row {"builderVersion":"5.2.1"} --><!-- wp:divi/column --><!-- /wp:divi/column -->'
+                . '<!-- /wp:divi/row -->',
+            Serializer::block($block)
+        );
+        self::assertSame('<!-- wp:paragraph --><!-- /wp:paragraph -->', Serializer::block(Block::create('core/paragraph')));
+    }
+
+    public function testVoidBlockGettingAChildBecomesAPair(): void
+    {
+        $document = (new Parser())->parse('<!-- wp:divi/column {"a":1} /-->');
+        $column = $document->children()[0];
+
+        $column->insertChild(0, Block::create('divi/text'));
+
+        self::assertSame(
+            '<!-- wp:divi/column {"a":1} --><!-- wp:divi/text --><!-- /wp:divi/text --><!-- /wp:divi/column -->',
+            Serializer::document($document)
+        );
+    }
+
+    public function testInsertAndRemoveKeepSurroundingText(): void
+    {
+        $document = (new Parser())->parse("A<!-- wp:divi/text /-->\nB<!-- wp:divi/code /-->C");
+        [$text, $code] = $document->children();
+        $new = Block::create('divi/button');
+
+        $document->insertChild(1, $new);
+        self::assertSame(
+            "A<!-- wp:divi/text /-->\nB<!-- wp:divi/button --><!-- /wp:divi/button --><!-- wp:divi/code /-->C",
+            Serializer::document($document)
+        );
+        self::assertSame(2, $document->removeChild($code));
+        self::assertSame(0, $document->indexOf($text));
+        $document->insertChild(99, $code);
+        self::assertSame(2, $document->indexOf($code));
+
+        $empty = new Document();
+        $empty->append("\n");
+        $empty->insertChild(0, Block::create('divi/section'));
+        self::assertSame("\n<!-- wp:divi/section --><!-- /wp:divi/section -->", Serializer::document($empty));
+    }
+
+    public function testCopyIsDeepAndSerializesIdentically(): void
+    {
+        $content = '<!-- wp:divi/row {"a":1} --><!-- wp:divi/column /--><!-- /wp:divi/row -->';
+        $row = (new Parser())->parse($content)->children()[0];
+        $copy = $row->copy();
+
+        $copy->children()[0]->setAttrs(['b' => 2]);
+
+        self::assertSame($content, Serializer::block($row));
+        self::assertSame('<!-- wp:divi/row {"a":1} --><!-- wp:divi/column {"b":2} /--><!-- /wp:divi/row -->', Serializer::block($copy));
+    }
+}