diff --git a/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java b/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java
index c2f58389..21618f71 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/service/DocumentService.java
@@ -21,9 +21,7 @@ import org.raddatz.familienarchiv.model.ScriptType;
 import org.raddatz.familienarchiv.model.TrainingLabel;
 import org.raddatz.familienarchiv.model.Person;
 import org.raddatz.familienarchiv.model.Tag;
-import org.raddatz.familienarchiv.repository.CompletionStatsRow;
 import org.raddatz.familienarchiv.repository.DocumentRepository;
-import org.raddatz.familienarchiv.repository.TranscriptionBlockRepository;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Sort;
 import org.springframework.data.jpa.domain.Specification;
@@ -64,7 +62,7 @@ public class DocumentService {
     private final DocumentVersionService documentVersionService;
     private final AnnotationService annotationService;
     private final AuditService auditService;
-    private final TranscriptionBlockRepository transcriptionBlockRepository;
+    private final TranscriptionBlockQueryService transcriptionBlockQueryService;
     private final AuditLogQueryService auditLogQueryService;
 
     public record StoreResult(Document document, boolean isNew) {}
@@ -414,12 +412,7 @@ public class DocumentService {
     }
 
     private Map<UUID, Integer> fetchCompletionPercentages(List<UUID> docIds) {
-        if (docIds.isEmpty()) return Map.of();
-        Map<UUID, Integer> result = new HashMap<>();
-        for (CompletionStatsRow row : transcriptionBlockRepository.findCompletionStatsForDocuments(docIds)) {
-            result.put(row.getDocumentId(), row.getCompletionPercentage());
-        }
-        return result;
+        return transcriptionBlockQueryService.getCompletionStats(docIds);
     }
 
     private Sort resolveSort(DocumentSort sort, String dir) {
diff --git a/backend/src/main/java/org/raddatz/familienarchiv/service/TranscriptionBlockQueryService.java b/backend/src/main/java/org/raddatz/familienarchiv/service/TranscriptionBlockQueryService.java
new file mode 100644
index 00000000..945b45d7
--- /dev/null
+++ b/backend/src/main/java/org/raddatz/familienarchiv/service/TranscriptionBlockQueryService.java
@@ -0,0 +1,27 @@
+package org.raddatz.familienarchiv.service;
+
+import lombok.RequiredArgsConstructor;
+import org.raddatz.familienarchiv.repository.CompletionStatsRow;
+import org.raddatz.familienarchiv.repository.TranscriptionBlockRepository;
+import org.springframework.stereotype.Service;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+@Service
+@RequiredArgsConstructor
+public class TranscriptionBlockQueryService {
+
+    private final TranscriptionBlockRepository blockRepository;
+
+    public Map<UUID, Integer> getCompletionStats(List<UUID> documentIds) {
+        if (documentIds.isEmpty()) return Map.of();
+        Map<UUID, Integer> result = new HashMap<>();
+        for (CompletionStatsRow row : blockRepository.findCompletionStatsForDocuments(documentIds)) {
+            result.put(row.getDocumentId(), row.getCompletionPercentage());
+        }
+        return result;
+    }
+}
diff --git a/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceSortTest.java b/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceSortTest.java
index 2deee90f..b3905d0e 100644
--- a/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceSortTest.java
+++ b/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceSortTest.java
@@ -11,7 +11,6 @@ import org.raddatz.familienarchiv.dto.DocumentSort;
 import org.raddatz.familienarchiv.model.Document;
 import org.raddatz.familienarchiv.model.DocumentStatus;
 import org.raddatz.familienarchiv.repository.DocumentRepository;
-import org.raddatz.familienarchiv.repository.TranscriptionBlockRepository;
 import org.springframework.data.domain.Sort;
 import org.springframework.data.jpa.domain.Specification;
 
@@ -33,7 +32,7 @@ class DocumentServiceSortTest {
     @Mock DocumentVersionService documentVersionService;
     @Mock AnnotationService annotationService;
     @Mock AuditLogQueryService auditLogQueryService;
-    @Mock TranscriptionBlockRepository transcriptionBlockRepository;
+    @Mock TranscriptionBlockQueryService transcriptionBlockQueryService;
     @InjectMocks DocumentService documentService;
 
     // ─── searchDocuments — DATE sort ──────────────────────────────────────────
diff --git a/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceTest.java b/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceTest.java
index 396a7362..6a3aec0f 100644
--- a/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceTest.java
+++ b/backend/src/test/java/org/raddatz/familienarchiv/service/DocumentServiceTest.java
@@ -22,7 +22,6 @@ import org.raddatz.familienarchiv.model.DocumentStatus;
 import org.raddatz.familienarchiv.model.Person;
 import org.raddatz.familienarchiv.model.Tag;
 import org.raddatz.familienarchiv.repository.DocumentRepository;
-import org.raddatz.familienarchiv.repository.TranscriptionBlockRepository;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageImpl;
 import org.springframework.data.domain.Pageable;
@@ -55,7 +54,7 @@ class DocumentServiceTest {
     @Mock AnnotationService annotationService;
     @Mock AuditService auditService;
     @Mock AuditLogQueryService auditLogQueryService;
-    @Mock TranscriptionBlockRepository transcriptionBlockRepository;
+    @Mock TranscriptionBlockQueryService transcriptionBlockQueryService;
     @InjectMocks DocumentService documentService;
 
     // ─── deleteDocument ───────────────────────────────────────────────────────
diff --git a/frontend/src/lib/components/ContributorStack.svelte b/frontend/src/lib/components/ContributorStack.svelte
index 3204a7dc..6bb70fd2 100644
--- a/frontend/src/lib/components/ContributorStack.svelte
+++ b/frontend/src/lib/components/ContributorStack.svelte
@@ -38,6 +38,8 @@ function safeColor(color: string): string {
 		{/each}
 		{#if hasMore}
 			<span
+				role="img"
+				aria-label="Weitere Mitwirkende"
 				class="-ml-1.5 inline-flex h-[22px] w-[22px] flex-shrink-0 items-center justify-center rounded-full bg-[#e4e2d7] font-sans text-xs font-bold text-ink-3 ring-2 ring-white"
 			>
 				…
diff --git a/frontend/src/lib/components/DashboardResumeStrip.svelte b/frontend/src/lib/components/DashboardResumeStrip.svelte
index e9c7620f..76eade81 100644
--- a/frontend/src/lib/components/DashboardResumeStrip.svelte
+++ b/frontend/src/lib/components/DashboardResumeStrip.svelte
@@ -7,6 +7,10 @@ interface Props {
 }
 
 const { resumeDoc }: Props = $props();
+
+function safeColor(color: string): string {
+	return /^#[0-9a-fA-F]{6}$/.test(color) ? color : '#8c9aa3';
+}
 </script>
 
 {#if resumeDoc === null}
@@ -94,7 +98,7 @@ const { resumeDoc }: Props = $props();
 				{#each resumeDoc.collaborators.slice(0, 3) as collab (collab.initials + collab.color)}
 					<span
 						class="-ml-1 inline-flex h-6 w-6 items-center justify-center rounded-full font-sans text-[10px] font-bold text-white ring-2 ring-white"
-						style="background:{collab.color}">{collab.initials}</span
+						style="background:{safeColor(collab.color)}">{collab.initials}</span
 					>
 				{/each}
 			</div>
diff --git a/frontend/src/lib/components/DocumentRow.svelte b/frontend/src/lib/components/DocumentRow.svelte
index d4f9534b..bee37ac5 100644
--- a/frontend/src/lib/components/DocumentRow.svelte
+++ b/frontend/src/lib/components/DocumentRow.svelte
@@ -29,6 +29,10 @@ function tagClass(matched: boolean): string {
 		? 'inline-flex items-center gap-1 rounded px-2 py-1.5 text-xs font-bold tracking-widest uppercase bg-primary text-primary-fg transition-colors'
 		: 'inline-flex items-center gap-1 rounded px-2 py-1.5 text-xs font-bold tracking-widest uppercase bg-muted text-ink hover:bg-primary hover:text-primary-fg transition-colors';
 }
+
+function safeTagColor(color: string | null | undefined): string {
+	return color && /^#[0-9a-fA-F]{6}$/.test(color) ? color : '#cdcbbf';
+}
 </script>
 
 <li class="group transition-colors duration-200 hover:bg-muted/50">
@@ -52,7 +56,10 @@ function tagClass(matched: boolean): string {
 
 				<!-- Snippet -->
 				{#if snippetSegments}
-					<p class="mb-2 line-clamp-2 font-sans text-sm text-ink-2 italic">
+					<p
+						data-testid="search-snippet"
+						class="mb-2 line-clamp-2 font-sans text-sm text-ink-2 italic"
+					>
 						{#each snippetSegments as seg, i (i)}
 							{#if seg.highlight}
 								<mark
@@ -117,7 +124,9 @@ function tagClass(matched: boolean): string {
 								onclick={(e) => { e.stopPropagation(); goto('/documents?tag=' + encodeURIComponent(tag.name)); }}
 							>
 								{#if tag.color}
-									<span class="h-1.5 w-1.5 rounded-full" style="background-color: {tag.color};"
+									<span
+										class="h-1.5 w-1.5 rounded-full"
+										style="background-color: {safeTagColor(tag.color)};"
 									></span>
 								{/if}
 								{tag.name}
diff --git a/frontend/src/routes/DocumentList.svelte b/frontend/src/routes/DocumentList.svelte
index bf930769..6db4c8c4 100644
--- a/frontend/src/routes/DocumentList.svelte
+++ b/frontend/src/routes/DocumentList.svelte
@@ -74,7 +74,7 @@ const yearGroups = $derived.by(() => {
 			class="mb-4 overflow-hidden border border-line bg-surface shadow-sm"
 		>
 			<div class="border-b border-line bg-muted px-5 py-2">
-				<span class="font-sans text-[10px] font-bold tracking-widest text-ink-3 uppercase"
+				<span class="font-sans text-xs font-bold tracking-widest text-ink-3 uppercase"
 					>{group.year}</span
 				>
 			</div>