diff --git a/src/Integrations/Divi/BlockTree/NodeSummary.php b/src/Integrations/Divi/BlockTree/NodeSummary.php
index e503f6f..d8fbdaf 100644
--- a/src/Integrations/Divi/BlockTree/NodeSummary.php
+++ b/src/Integrations/Divi/BlockTree/NodeSummary.php
@@ -23,6 +23,12 @@ final class NodeSummary
     /** The admin label is a one-line title in the layers panel, never an unbounded copy. */
     private const LABEL_LIMIT = 80;
 
+    /** "font-body" for the group name "divi/font-body" – the key "group_presets" of the write tools takes. */
+    public static function groupShortName(string $groupName): string
+    {
+        return str_starts_with($groupName, 'divi/') ? substr($groupName, 5) : $groupName;
+    }
+
     public static function label(Block $block): string
     {
         $attrs = $block->name() === 'divi/global-layout' && is_array($block->attrs()['localAttrs'] ?? null)
diff --git a/src/Integrations/Divi/BlockTree/Outline.php b/src/Integrations/Divi/BlockTree/Outline.php
index bec980d..2ba5c7c 100644
--- a/src/Integrations/Divi/BlockTree/Outline.php
+++ b/src/Integrations/Divi/BlockTree/Outline.php
@@ -174,8 +174,7 @@ final class Outline
     {
         $lines = [];
         foreach (NodeSummary::groupPresets($block) as $group) {
-            $name = $group['groupName'];
-            $short = str_starts_with($name, 'divi/') ? substr($name, 5) : $name;
+            $short = NodeSummary::groupShortName($group['groupName']);
             $lines[] = $short . ': ' . implode(', ', $this->namesOf($group['presetIds']));
         }
 
diff --git a/src/Integrations/Divi/Design/ModuleUsageQuery.php b/src/Integrations/Divi/Design/ModuleUsageQuery.php
index fb22dde..c7ebc3b 100644
--- a/src/Integrations/Divi/Design/ModuleUsageQuery.php
+++ b/src/Integrations/Divi/Design/ModuleUsageQuery.php
@@ -23,8 +23,6 @@ final class ModuleUsageQuery implements UsageQuery
 {
     private const NAME = '/^([a-z][a-z0-9_-]*)\/([a-z][a-z0-9_-]*)$/D';
 
-    private const ESCAPED_LETTER = '\\\\u00[4-7][0-9a-fA-F]';
-
     /** @throws InvalidArgumentException When $module is no full block name such as "divi/button". */
     public function __construct(private string $module)
     {
@@ -39,7 +37,7 @@ final class ModuleUsageQuery implements UsageQuery
             '(post_content LIKE %s OR post_content REGEXP %s OR post_content REGEXP %s)',
             '%' . $db->esc_like($this->module) . '%',
             $this->escapedSlash(),
-            self::ESCAPED_LETTER
+            self::ESCAPED_LETTER_REGEX
         );
     }
 
diff --git a/src/Integrations/Divi/Design/PresetAssignment.php b/src/Integrations/Divi/Design/PresetAssignment.php
index ae32fc2..22c77e6 100644
--- a/src/Integrations/Divi/Design/PresetAssignment.php
+++ b/src/Integrations/Divi/Design/PresetAssignment.php
@@ -6,6 +6,7 @@ namespace LIT\MCP\Integrations\Divi\Design;
 
 use Closure;
 use InvalidArgumentException;
+use LIT\MCP\Integrations\Divi\BlockTree\NodeSummary;
 
 defined('ABSPATH') || exit;
 
@@ -280,7 +281,7 @@ final class PresetAssignment
     private static function shortNames(array $groups): string
     {
         $names = array_unique(array_map(
-            static fn (string $name): string => str_starts_with($name, 'divi/') ? substr($name, 5) : $name,
+            NodeSummary::groupShortName(...),
             array_values($groups)
         ));
 
diff --git a/src/Integrations/Divi/Design/PresetUsageQuery.php b/src/Integrations/Divi/Design/PresetUsageQuery.php
index 6619bc1..ba827b6 100644
--- a/src/Integrations/Divi/Design/PresetUsageQuery.php
+++ b/src/Integrations/Divi/Design/PresetUsageQuery.php
@@ -18,8 +18,6 @@ defined('ABSPATH') || exit;
  */
 final class PresetUsageQuery implements UsageQuery
 {
-    private const ESCAPED_LETTER = '\\\\u00[4-7][0-9a-fA-F]';
-
     /** @var list<array{scope: PresetScope, id: string, default: bool}> */
     private array $targets;
 
@@ -61,7 +59,7 @@ final class PresetUsageQuery implements UsageQuery
 
         return (string) $db->prepare(
             '(' . str_repeat('post_content LIKE %s OR ', count($likes)) . 'post_content REGEXP %s)',
-            ...array_merge($likes, [self::ESCAPED_LETTER])
+            ...array_merge($likes, [self::ESCAPED_LETTER_REGEX])
         );
     }
 
diff --git a/src/Integrations/Divi/Library/LibraryUsageQuery.php b/src/Integrations/Divi/Library/LibraryUsageQuery.php
index 9a34d84..d78c352 100644
--- a/src/Integrations/Divi/Library/LibraryUsageQuery.php
+++ b/src/Integrations/Divi/Library/LibraryUsageQuery.php
@@ -23,7 +23,7 @@ final class LibraryUsageQuery implements UsageQuery
             '(LOWER(post_content) LIKE %s OR LOWER(post_content) LIKE %s OR post_content REGEXP %s)',
             '%' . $db->esc_like('globalmodule') . '%',
             '%' . $db->esc_like('global_module') . '%',
-            str_repeat(chr(92), 2) . 'u00[4-7][0-9a-fA-F]'
+            self::ESCAPED_LETTER_REGEX
         );
     }
 
diff --git a/src/Integrations/Divi/Library/UsageQuery.php b/src/Integrations/Divi/Library/UsageQuery.php
index d208777..d7d4c07 100644
--- a/src/Integrations/Divi/Library/UsageQuery.php
+++ b/src/Integrations/Divi/Library/UsageQuery.php
@@ -13,6 +13,12 @@ defined('ABSPATH') || exit;
  */
 interface UsageQuery
 {
+    /**
+     * MySQL REGEXP for a JSON-escaped letter ("\\u004x" … "\\u007x"): a name or ID written that way is not found by
+     * LIKE, so candidate conditions keep such posts (fail closed, ruling P23).
+     */
+    public const ESCAPED_LETTER_REGEX = '\\\\u00[4-7][0-9a-fA-F]';
+
     /** A condition for "WHERE (…)", already passed through $db->prepare(). */
     public function candidateCondition(\wpdb $db): string;
 
diff --git a/src/Integrations/Divi/Pages/DiviComposition.php b/src/Integrations/Divi/Pages/DiviComposition.php
index 9a2a31d..e09145c 100644
--- a/src/Integrations/Divi/Pages/DiviComposition.php
+++ b/src/Integrations/Divi/Pages/DiviComposition.php
@@ -115,9 +115,8 @@ class DiviComposition
 
     /**
      * The one PresetAssignment of this composition (D7, rulings R2, R3): the book comes lazily from Divi's stored
-     * presets, ids must pass the choke point unchanged.
-     *
-     * @internal Public for tests; code uses composer() / warnings().
+     * presets, ids must pass the choke point unchanged. Public: DiviIntegration::presetAssignment() hands it to
+     * the site-wide tools (lit/divi-presets-assign), which need the same instance as the write tools.
      */
     public function presets(): PresetAssignment
     {
diff --git a/src/Integrations/Divi/Pages/DiviNodeGetAbility.php b/src/Integrations/Divi/Pages/DiviNodeGetAbility.php
index 719e0ec..ee713c1 100644
--- a/src/Integrations/Divi/Pages/DiviNodeGetAbility.php
+++ b/src/Integrations/Divi/Pages/DiviNodeGetAbility.php
@@ -202,10 +202,9 @@ final class DiviNodeGetAbility implements Ability
     {
         $groups = [];
         foreach (NodeSummary::groupPresets($block) as $groupId => $group) {
-            $name = $group['groupName'];
             $groups[] = [
                 'group_id' => $groupId,
-                'group' => str_starts_with($name, 'divi/') ? substr($name, 5) : $name,
+                'group' => NodeSummary::groupShortName($group['groupName']),
                 'presets' => array_map(
                     static fn (string $presetId): array => ['id' => $presetId, 'name' => $names[$presetId] ?? ''],
                     $group['presetIds']
diff --git a/src/Integrations/Divi/Pages/DiviUpdateAbility.php b/src/Integrations/Divi/Pages/DiviUpdateAbility.php
index 0bfd77f..1d1d231 100644
--- a/src/Integrations/Divi/Pages/DiviUpdateAbility.php
+++ b/src/Integrations/Divi/Pages/DiviUpdateAbility.php
@@ -38,7 +38,8 @@ final class DiviUpdateAbility extends DiviWriteAbility
         return 'Ändert vorhandene Divi-Knoten: changes = Liste von {id, set: {Kurzform-Felder}, attrs: {Attributpfad: '
             . '{Breakpoint: Wert}}, preset, group_presets, clear_overrides, label}. null entfernt einen Wert. '
             . 'preset = Name/ID oder Liste (Stapel, bis ' . PresetAssignment::MAX_STACK . '; bei gleicher Priorität '
-            . 'gewinnt das letzte Preset im Stapel); group_presets = {Gruppe: Preset}, z. B. {"font-body": "Fließtext"}. Überdecken lokale Werte '
+            . 'gewinnt das letzte Preset im Stapel); group_presets = {Gruppe: Preset}, z. B. '
+            . '{"font-body": "Fließtext"}. Überdecken lokale Werte '
             . 'ein Preset, meldet die Antwort das; clear_overrides: true entfernt sie (nach set/attrs). Nicht '
             . 'genannte Einstellungen bleiben unverändert. Jeder Knoten nur einmal pro Aufruf; denselben Pfad nicht '
             . 'zugleich über set und attrs. tree_rev aus lit-divi-outline ist Pflicht; alles oder nichts.';
diff --git a/tests/Unit/Integrations/Divi/BlockTree/NodeSummaryTest.php b/tests/Unit/Integrations/Divi/BlockTree/NodeSummaryTest.php
index f7b0015..f5d9ef7 100644
--- a/tests/Unit/Integrations/Divi/BlockTree/NodeSummaryTest.php
+++ b/tests/Unit/Integrations/Divi/BlockTree/NodeSummaryTest.php
@@ -64,4 +64,11 @@ final class NodeSummaryTest extends TestCase
         self::assertSame([], NodeSummary::groupPresets(Block::create('divi/text', ['groupPreset' => 'x'])));
         self::assertSame([], NodeSummary::groupPresets(Block::create('divi/text', ['groupPreset' => []])));
     }
+
+    public function testGroupShortNameDropsTheDiviPrefixOnly(): void
+    {
+        self::assertSame('font-body', NodeSummary::groupShortName('divi/font-body'));
+        self::assertSame('custom/x', NodeSummary::groupShortName('custom/x'));
+        self::assertSame('spacing', NodeSummary::groupShortName('spacing'));
+    }
 }
diff --git a/tests/Unit/Integrations/Divi/Compose/WarningsTest.php b/tests/Unit/Integrations/Divi/Compose/WarningsTest.php
index 5989476..ac72e5f 100644
--- a/tests/Unit/Integrations/Divi/Compose/WarningsTest.php
+++ b/tests/Unit/Integrations/Divi/Compose/WarningsTest.php
@@ -132,6 +132,35 @@ final class WarningsTest extends TestCase
         self::assertStringEndsWith('clear_overrides: true entfernt sie.', $covering[0]);
     }
 
+    /** A group preset only triggered loading before: its values are overridden by local ones like a module preset's. */
+    public function testWarnsWhenLocalValuesCoverAGroupPreset(): void
+    {
+        $path = 'button.decoration.font.font';
+        $book = PresetBook::fromDivi(['group' => ['divi/font' => ['default' => '', 'items' => [
+            'g-1' => [
+                'type' => 'group', 'id' => 'g-1', 'name' => 'Fließtext groß', 'groupName' => 'divi/font',
+                'groupId' => $path, 'moduleName' => 'divi/button',
+                'attrs' => ['button' => ['decoration' => ['font' => ['font' => [
+                    'desktop' => ['value' => ['color' => '#ffffff']],
+                ]]]]],
+            ],
+        ]]]]);
+        $presets = ComposeFixture::presetAssignment(null, null, null, null, static fn (): PresetBook => $book);
+        $button = Block::create('divi/button', [
+            'groupPreset' => [$path => ['presetId' => ['g-1'], 'groupName' => 'divi/font']],
+            'button' => ['decoration' => ['font' => ['font' => ['desktop' => ['value' => ['color' => '#000000']]]]]],
+        ]);
+
+        [$covering, $index] = self::collect([$button], [$button], $presets);
+
+        self::assertCount(1, $covering);
+        self::assertStringStartsWith(
+            $index->idOf($button) . ': lokale Werte überdecken „Fließtext groß“: ',
+            $covering[0]
+        );
+        self::assertStringContainsString($path, $covering[0]);
+    }
+
     public function testEqualValuesAndUntouchedBlocksDoNotWarn(): void
     {
         $loads = 0;
diff --git a/tests/Unit/Integrations/Divi/Library/LibraryUsageQueryTest.php b/tests/Unit/Integrations/Divi/Library/LibraryUsageQueryTest.php
index fe0103e..6ca49d7 100644
--- a/tests/Unit/Integrations/Divi/Library/LibraryUsageQueryTest.php
+++ b/tests/Unit/Integrations/Divi/Library/LibraryUsageQueryTest.php
@@ -4,12 +4,23 @@ declare(strict_types=1);
 
 namespace LIT\MCP\Tests\Unit\Integrations\Divi\Library;
 
+use LIT\MCP\Integrations\Divi\Design\ModuleUsageQuery;
+use LIT\MCP\Integrations\Divi\Design\PresetUsageQuery;
 use LIT\MCP\Integrations\Divi\Library\LibraryUsageQuery;
+use LIT\MCP\Integrations\Divi\Library\UsageQuery;
 use LIT\MCP\Tests\Unit\TestCase;
 use Mockery;
 
 final class LibraryUsageQueryTest extends TestCase
 {
+    /** The one fail-closed pattern for JSON-escaped letters (two backslashes, "u00", a letter range). */
+    public function testEscapedLetterPatternIsPinned(): void
+    {
+        self::assertSame(str_repeat(chr(92), 2) . 'u00[4-7][0-9a-fA-F]', UsageQuery::ESCAPED_LETTER_REGEX);
+        self::assertSame(UsageQuery::ESCAPED_LETTER_REGEX, ModuleUsageQuery::ESCAPED_LETTER_REGEX);
+        self::assertSame(UsageQuery::ESCAPED_LETTER_REGEX, PresetUsageQuery::ESCAPED_LETTER_REGEX);
+    }
+
     public function testConditionIsTheFormerCandidateFilter(): void
     {
         $db = Mockery::mock(\wpdb::class);