diff --git a/build.gradle b/build.gradle
index fd706cb6c..0f30b3d67 100644
--- a/build.gradle
+++ b/build.gradle
@@ -67,7 +67,7 @@ springBoot {
 
 allprojects {
     group = 'stirling.software'
-    version = '2.5.0'
+    version = '2.5.1'
 
     configurations.configureEach {
         exclude group: 'commons-logging', module: 'commons-logging'
diff --git a/frontend/src-tauri/tauri.conf.json b/frontend/src-tauri/tauri.conf.json
index 7c5b3d957..410e25f3b 100644
--- a/frontend/src-tauri/tauri.conf.json
+++ b/frontend/src-tauri/tauri.conf.json
@@ -1,7 +1,7 @@
 {
     "$schema": "../node_modules/@tauri-apps/cli/config.schema.json",
     "productName": "Stirling-PDF",
-    "version": "2.5.0",
+    "version": "2.5.1",
     "identifier": "stirling.pdf.dev",
     "build": {
         "frontendDist": "../dist",
diff --git a/frontend/src/core/components/shared/LanguageSelector.tsx b/frontend/src/core/components/shared/LanguageSelector.tsx
index 1eabfcf1f..66aa17c8a 100644
--- a/frontend/src/core/components/shared/LanguageSelector.tsx
+++ b/frontend/src/core/components/shared/LanguageSelector.tsx
@@ -52,12 +52,15 @@ const LanguageItem: React.FC<LanguageItemProps> = ({
 }) => {
   const { t } = useTranslation();
 
+  const labelText = option.label;
+  const comingSoonText = t('comingSoon', 'Coming soon');
+
   const label = disabled ? (
-    <Tooltip content={t('comingSoon', 'Coming soon')} position="left" arrow>
-      <p>{option.label}</p>
+    <Tooltip content={comingSoonText} position="left" arrow>
+      <p>{labelText}</p>
     </Tooltip>
   ) : (
-    <p>{option.label}</p>
+    <p>{labelText}</p>
   );
 
   return (
@@ -157,12 +160,27 @@ const LanguageSelector: React.FC<LanguageSelectorProps> = ({
   compact = false,
   tooltip
 }) => {
-  const { i18n } = useTranslation();
+  const { i18n, ready } = useTranslation();
   const [opened, setOpened] = useState(false);
   const [animationTriggered, setAnimationTriggered] = useState(false);
   const [pendingLanguage, setPendingLanguage] = useState<string | null>(null);
   const [rippleEffect, setRippleEffect] = useState<RippleEffect | null>(null);
 
+  // Trigger animation when dropdown opens
+  useEffect(() => {
+    if (opened) {
+      setAnimationTriggered(false);
+      // Small delay to ensure DOM is ready
+      setTimeout(() => setAnimationTriggered(true), 20);
+    }
+  }, [opened]);
+
+  // Don't render until i18n is ready to prevent race condition
+  // during SAML auth where components render before i18n initializes
+  if (!ready || !i18n.language) {
+    return null;
+  }
+
   // Get the filtered list of supported languages from i18n
   // This respects server config (ui.languages) applied by AppConfigLoader
   const allowedLanguages = (i18n.options.supportedLngs as string[] || [])
@@ -176,12 +194,6 @@ const LanguageSelector: React.FC<LanguageSelectorProps> = ({
       label: name,
     }));
 
-  // Hide the language selector if there's only one language option
-  // (no point showing a selector when there's nothing to select)
-  if (languageOptions.length <= 1) {
-    return null;
-  }
-
   // Calculate dropdown width and grid columns based on number of languages
   // 2-4: 300px/2 cols, 5-9: 400px/3 cols, 10+: 600px/4 cols
   const dropdownWidth = languageOptions.length <= 4 ? 300
@@ -225,16 +237,14 @@ const LanguageSelector: React.FC<LanguageSelectorProps> = ({
   };
 
   const currentLanguage = supportedLanguages[i18n.language as keyof typeof supportedLanguages] ||
-                         supportedLanguages['en-GB'];
+                         supportedLanguages['en-GB'] ||
+                         'English'; // Fallback if supportedLanguages lookup fails
 
-  // Trigger animation when dropdown opens
-  useEffect(() => {
-    if (opened) {
-      setAnimationTriggered(false);
-      // Small delay to ensure DOM is ready
-      setTimeout(() => setAnimationTriggered(true), 20);
-    }
-  }, [opened]);
+  // Hide the language selector if there's only one language option
+  // (no point showing a selector when there's nothing to select)
+  if (languageOptions.length <= 1) {
+    return null;
+  }
 
   return (
     <>
diff --git a/frontend/src/core/components/shared/ToolChain.tsx b/frontend/src/core/components/shared/ToolChain.tsx
index d3c25f653..c67d89427 100644
--- a/frontend/src/core/components/shared/ToolChain.tsx
+++ b/frontend/src/core/components/shared/ToolChain.tsx
@@ -24,9 +24,8 @@ const ToolChain: React.FC<ToolChainProps> = ({
   size = 'xs',
   color = 'var(--mantine-color-blue-7)'
 }) => {
-  if (!toolChain || toolChain.length === 0) return null;
-
   const { t } = useTranslation();
+  if (!toolChain || toolChain.length === 0) return null;
 
   const toolIds = toolChain.map(tool => tool.toolId);
 
diff --git a/frontend/src/core/components/tools/compare/CompareDocumentPane.tsx b/frontend/src/core/components/tools/compare/CompareDocumentPane.tsx
index 18adf6ac6..c541c60f2 100644
--- a/frontend/src/core/components/tools/compare/CompareDocumentPane.tsx
+++ b/frontend/src/core/components/tools/compare/CompareDocumentPane.tsx
@@ -74,6 +74,11 @@ const CompareDocumentPane = ({
     }
   }, [zoom]);
 
+  const renderedPageNumbers = useMemo(
+    () => new Set(pages.map((p) => p.pageNumber)),
+    [pages]
+  );
+
   return (
     <div className="compare-pane">
       <div className="compare-header">
@@ -88,7 +93,7 @@ const CompareDocumentPane = ({
                 placeholder={dropdownPlaceholder ?? null}
                 className={pane === 'comparison' ? 'compare-changes-select--comparison' : undefined}
                 onNavigate={onNavigateChange}
-                renderedPageNumbers={useMemo(() => new Set(pages.map(p => p.pageNumber)), [pages])}
+                renderedPageNumbers={renderedPageNumbers}
               />
             )}
           </Group>
diff --git a/frontend/src/core/components/tools/editTableOfContents/EditTableOfContentsWorkbenchView.tsx b/frontend/src/core/components/tools/editTableOfContents/EditTableOfContentsWorkbenchView.tsx
index d6c80cf62..3cbc3979c 100644
--- a/frontend/src/core/components/tools/editTableOfContents/EditTableOfContentsWorkbenchView.tsx
+++ b/frontend/src/core/components/tools/editTableOfContents/EditTableOfContentsWorkbenchView.tsx
@@ -43,6 +43,16 @@ interface EditTableOfContentsWorkbenchViewProps {
 const EditTableOfContentsWorkbenchView = ({ data }: EditTableOfContentsWorkbenchViewProps) => {
   const { t } = useTranslation();
   const terminology = useFileActionTerminology();
+  const files = data?.files ?? [];
+  const thumbnails = data?.thumbnails ?? [];
+  const previewFiles = useMemo(
+    () =>
+      files.map((file, index) => ({
+        file,
+        thumbnail: thumbnails[index],
+      })),
+    [files, thumbnails]
+  );
 
   if (!data) {
     return (
@@ -63,8 +73,6 @@ const EditTableOfContentsWorkbenchView = ({ data }: EditTableOfContentsWorkbench
     bookmarks,
     selectedFileName,
     disabled,
-    files,
-    thumbnails,
     downloadUrl,
     downloadFilename,
     errorMessage,
@@ -78,15 +86,6 @@ const EditTableOfContentsWorkbenchView = ({ data }: EditTableOfContentsWorkbench
     onFileClick,
   } = data;
 
-  const previewFiles = useMemo(
-    () =>
-      files?.map((file, index) => ({
-        file,
-        thumbnail: thumbnails[index],
-      })) ?? [],
-    [files, thumbnails]
-  );
-
   const showResults = Boolean(
     previewFiles.length > 0 || downloadUrl || errorMessage
   );
diff --git a/frontend/src/core/components/tools/shared/FilesToolStep.tsx b/frontend/src/core/components/tools/shared/FilesToolStep.tsx
index b1e8933f5..1d71196ac 100644
--- a/frontend/src/core/components/tools/shared/FilesToolStep.tsx
+++ b/frontend/src/core/components/tools/shared/FilesToolStep.tsx
@@ -1,7 +1,7 @@
 import React from 'react';
-import { useTranslation } from 'react-i18next';
 import FileStatusIndicator from '@app/components/tools/shared/FileStatusIndicator';
 import { StirlingFile } from '@app/types/fileContext';
+import i18n from '@app/i18n';
 
 export interface FilesToolStepProps {
   selectedFiles: StirlingFile[];
@@ -14,9 +14,7 @@ export function createFilesToolStep(
   createStep: (title: string, props: any, children?: React.ReactNode) => React.ReactElement,
   props: FilesToolStepProps
 ): React.ReactElement {
-  const { t } = useTranslation();
-
-  return createStep(t("files.title", "Files"), {
+  return createStep(i18n.t("files.title", "Files"), {
     isVisible: true,
     isCollapsed: props.isCollapsed,
     onCollapsedClick: props.onCollapsedClick
diff --git a/frontend/src/core/components/tools/shared/ReviewToolStep.tsx b/frontend/src/core/components/tools/shared/ReviewToolStep.tsx
index 7b324d5dc..c67d933f1 100644
--- a/frontend/src/core/components/tools/shared/ReviewToolStep.tsx
+++ b/frontend/src/core/components/tools/shared/ReviewToolStep.tsx
@@ -12,6 +12,7 @@ import { useFileActionIcons } from "@app/hooks/useFileActionIcons";
 import { saveOperationResults } from "@app/services/operationResultsSaveService";
 import { useFileActions, useFileState } from "@app/contexts/FileContext";
 import { FileId } from "@app/types/fileContext";
+import i18n from "@app/i18n";
 
 export interface ReviewToolStepProps<TParams = unknown> {
   isVisible: boolean;
@@ -151,10 +152,8 @@ export function createReviewToolStep<TParams = unknown>(
   ) => React.ReactElement,
   props: ReviewToolStepProps<TParams>
 ): React.ReactElement {
-  const { t } = useTranslation();
-
   return createStep(
-    t("review", "Review"),
+    i18n.t("review", "Review"),
     {
       isVisible: props.isVisible,
       isCollapsed: props.isCollapsed,
diff --git a/frontend/src/core/components/tools/shared/ToolStep.tsx b/frontend/src/core/components/tools/shared/ToolStep.tsx
index 89c39aad8..8d2d95513 100644
--- a/frontend/src/core/components/tools/shared/ToolStep.tsx
+++ b/frontend/src/core/components/tools/shared/ToolStep.tsx
@@ -80,8 +80,6 @@ const ToolStep = ({
   alwaysShowTooltip = false,
   tooltip
 }: ToolStepProps) => {
-  if (!isVisible) return null;
-
   const parent = useContext(ToolStepContext);
 
   // Auto-detect if we should show numbers based on sibling count or force option
@@ -91,6 +89,8 @@ const ToolStep = ({
     return parent ? parent.visibleStepCount >= 3 : false; // Auto-detect
   }, [showNumber, parent]);
 
+  if (!isVisible) return null;
+
   const stepNumber = _stepNumber;
 
   return (
diff --git a/frontend/src/core/testing/serverExperienceSimulations.ts b/frontend/src/core/testing/serverExperienceSimulations.ts
index 9a922911b..42cd297bc 100644
--- a/frontend/src/core/testing/serverExperienceSimulations.ts
+++ b/frontend/src/core/testing/serverExperienceSimulations.ts
@@ -38,7 +38,7 @@ const FREE_LICENSE_INFO: LicenseInfo = {
 
 const BASE_NO_LOGIN_CONFIG: AppConfig = {
   enableAnalytics: true,
-  appVersion: '2.5.0',
+  appVersion: '2.5.1',
   serverCertificateEnabled: false,
   enableAlphaFunctionality: false,
   serverPort: 8080,
diff --git a/frontend/src/proprietary/testing/serverExperienceSimulations.ts b/frontend/src/proprietary/testing/serverExperienceSimulations.ts
index e866976d5..3356759ba 100644
--- a/frontend/src/proprietary/testing/serverExperienceSimulations.ts
+++ b/frontend/src/proprietary/testing/serverExperienceSimulations.ts
@@ -48,7 +48,7 @@ const FREE_LICENSE_INFO: LicenseInfo = {
 
 const BASE_NO_LOGIN_CONFIG: AppConfig = {
   enableAnalytics: true,
-  appVersion: '2.5.0',
+  appVersion: '2.5.1',
   serverCertificateEnabled: false,
   enableAlphaFunctionality: false,
   enableDesktopInstallSlide: true,
diff --git a/testing/compose/docker-compose-keycloak-saml.yml b/testing/compose/docker-compose-keycloak-saml.yml
index d4a909877..c5192122c 100644
--- a/testing/compose/docker-compose-keycloak-saml.yml
+++ b/testing/compose/docker-compose-keycloak-saml.yml
@@ -74,7 +74,7 @@ services:
       DOCKER_ENABLE_SECURITY: "true"
       SECURITY_ENABLELOGIN: "true"
       SECURITY_LOGINMETHOD: "${SECURITY_LOGINMETHOD:-all}"
-      SYSTEM_DEFAULTLOCALE: en-US
+      SYSTEM_DEFAULTLOCALE: "${SYSTEM_DEFAULTLOCALE:-en-US}"
       SYSTEM_BACKENDURL: "http://localhost:8080"
 
       # Enterprise License (required for SAML)
diff --git a/testing/compose/start-saml-test.sh b/testing/compose/start-saml-test.sh
index 6a77a03d3..8037ab838 100755
--- a/testing/compose/start-saml-test.sh
+++ b/testing/compose/start-saml-test.sh
@@ -13,24 +13,48 @@ echo -e "${BLUE}╚════════════════════
 echo ""
 
 AUTO_LOGIN=false
+DEFAULT_LANGUAGE="en-US"
 COMPOSE_UP_ARGS=(-d --build)
-for arg in "$@"; do
-    case "$arg" in
+while [[ $# -gt 0 ]]; do
+    case "$1" in
         --auto)
             AUTO_LOGIN=true
+            shift
             ;;
         --nobuild)
             COMPOSE_UP_ARGS=(-d)
+            shift
+            ;;
+        --language)
+            if [[ -z "${2:-}" ]]; then
+                echo -e "${RED}Missing value for --language${NC}"
+                exit 1
+            fi
+            DEFAULT_LANGUAGE="$2"
+            shift 2
+            ;;
+        --language=*)
+            DEFAULT_LANGUAGE="${1#*=}"
+            shift
+            ;;
+        -l)
+            if [[ -z "${2:-}" ]]; then
+                echo -e "${RED}Missing value for -l${NC}"
+                exit 1
+            fi
+            DEFAULT_LANGUAGE="$2"
+            shift 2
             ;;
         -h|--help)
-            echo "Usage: $0 [--auto] [--nobuild]"
+            echo "Usage: $0 [--auto] [--nobuild] [--language <locale>]"
             echo ""
             echo "  --auto     Enable SSO auto-login and force SAML-only login method"
             echo "  --nobuild  Skip building images (use existing images)"
+            echo "  --language Set system default locale (e.g. de-DE, sv-SE)"
             exit 0
             ;;
         *)
-            echo -e "${RED}Unknown option: $arg${NC}"
+            echo -e "${RED}Unknown option: $1${NC}"
             exit 1
             ;;
     esac
@@ -65,6 +89,10 @@ if [ "$AUTO_LOGIN" = true ]; then
     echo ""
 fi
 
+export SYSTEM_DEFAULTLOCALE="$DEFAULT_LANGUAGE"
+echo -e "${GREEN}✓ Default locale set to: ${SYSTEM_DEFAULTLOCALE}${NC}"
+echo ""
+
 echo -e "${YELLOW}▶ Starting Keycloak (SAML) containers...${NC}"
 docker-compose -f docker-compose-keycloak-saml.yml up "${COMPOSE_UP_ARGS[@]}" keycloak-saml-db keycloak-saml