Fix dark mode PDF (#3065)

Author: SamyPesse

.changeset/selfish-rules-yell.md

@@ -0,0 +1,5 @@
+---
+"gitbook": patch
+---
+
+Fix PDF generation when user has dark mode configured.

packages/gitbook/src/components/DocumentView/Tabs/Tabs.tsx

@@ -12,14 +12,15 @@ export function Tabs(props: BlockProps<DocumentBlockTabs>) {
     const tabs: TabsItem[] = [];
     const tabsBody: React.ReactNode[] = [];
 
-    block.nodes.forEach((tab) => {
+    block.nodes.forEach((tab, index) => {
         tabs.push({
             id: tab.meta?.id ?? tab.key!,
             title: tab.data.title ?? '',
         });
 
         tabsBody.push(
             <Blocks
+                key={tab.key ?? index}
                 nodes={tab.nodes}
                 document={document}
                 ancestorBlocks={[...ancestorBlocks, block, tab]}

packages/gitbook/src/components/PDF/PDFRootLayout.tsx

@@ -1,5 +1,6 @@
 import { CustomizationRootLayout } from '@/components/RootLayout';
 import { defaultCustomization } from '@/lib/utils';
+import { CustomizationThemeMode } from '@gitbook/api';
 import type { GitBookSiteContext, GitBookSpaceContext } from '@v2/lib/context';
 
 /**
@@ -16,6 +17,7 @@ export async function PDFRootLayout(props: {
             customization={
                 'customization' in context ? context.customization : defaultCustomization()
             }
+            forcedTheme={CustomizationThemeMode.Light}
         >
             {children}
         </CustomizationRootLayout>