diff --git a/apps/readest-app/package.json b/apps/readest-app/package.json
index 12daed14..95e237fb 100644
--- a/apps/readest-app/package.json
+++ b/apps/readest-app/package.json
@@ -46,7 +46,8 @@
     "update-metadata": "bash ./scripts/sync-release-notes.sh release-notes.json ../../data/metainfo/appdata.xml",
     "check:optional-chaining": "count=$(grep -rno '\\?\\.[a-zA-Z_$]' .next/static/chunks/* out/_next/static/chunks/* | wc -l); if [ \"$count\" -gt 0 ]; then echo '❌ Optional chaining found in output!'; exit 1; else echo '✅ No optional chaining found.'; fi",
     "check:translations": "count=$(grep -rno '__STRING_NOT_TRANSLATED__' public/locales/* | wc -l); if [ \"$count\" -gt 0 ]; then echo '❌ Untranslated strings found!'; exit 1; else echo '✅ All strings translated.'; fi",
-    "check:all": "pnpm check:translations",
+    "check:lookbehind-regex": "count=$(grep -rnoE '\\(\\?<[!=]' .next/static/chunks/* out/_next/static/chunks/* | wc -l); if [ \"$count\" -gt 0 ]; then echo '❌ Lookbehind regex found in output!'; exit 1; else echo '✅ No lookbehind regex found.'; fi",
+    "check:all": "pnpm check:translations && pnpm check:lookbehind-regex",
     "build-check": "pnpm build && pnpm build-web && pnpm check:all"
   },
   "dependencies": {
diff --git a/apps/readest-app/src/app/error.tsx b/apps/readest-app/src/app/error.tsx
index 422cafc2..9590e822 100644
--- a/apps/readest-app/src/app/error.tsx
+++ b/apps/readest-app/src/app/error.tsx
@@ -54,17 +54,27 @@ export default function Error({ error, reset }: ErrorPageProps) {
             )}
           </p>
 
-          <div className='alert alert-error mb-8'>
-            <div className='flex-col items-start text-left'>
+          <div className='alert alert-error mb-8 overflow-hidden'>
+            <div className='w-full min-w-0 flex-col items-start text-left'>
               <h3 className='mb-2 font-bold'>{_('Error Details:')}</h3>
-              <p className='break-words font-mono text-sm'>{error.message}</p>
-              {browserInfo && <p className='mt-2 font-mono text-sm'>Browser: {browserInfo}</p>}
+              <p className='overflow-wrap-anywhere w-full break-words font-mono text-sm'>
+                {error.message}
+              </p>
+              {browserInfo && (
+                <p className='overflow-wrap-anywhere mt-2 w-full break-words font-mono text-sm'>
+                  Browser: {browserInfo}
+                </p>
+              )}
               {error.stack && (
-                <p className='mt-2 whitespace-pre-wrap break-all font-mono text-sm'>
+                <p className='overflow-wrap-anywhere mt-2 w-full whitespace-pre-wrap break-words font-mono text-sm'>
                   {error.stack.split('\n').slice(0, 3).join('\n')}
                 </p>
               )}
-              {error.digest && <p className='mt-2 text-xs opacity-70'>Error ID: {error.digest}</p>}
+              {error.digest && (
+                <p className='overflow-wrap-anywhere mt-2 w-full break-words text-xs opacity-70'>
+                  Error ID: {error.digest}
+                </p>
+              )}
             </div>
           </div>
 
diff --git a/apps/readest-app/src/services/transformers/whitespace.ts b/apps/readest-app/src/services/transformers/whitespace.ts
index 62eb3789..720b2bb6 100644
--- a/apps/readest-app/src/services/transformers/whitespace.ts
+++ b/apps/readest-app/src/services/transformers/whitespace.ts
@@ -8,7 +8,7 @@ export const whitespaceTransformer: Transformer = {
     if (viewSettings.overrideLayout) {
       const cleaned = ctx.content
         // Replace &nbsp; but skip literal "&amp;nbsp;"
-        .replace(/(?<!&amp;)&nbsp;/g, ' ')
+        .replace(/(&amp;)?&nbsp;/g, (match, amp) => (amp ? match : ' '))
         // Replace literal non-breaking space characters (U+00A0) with normal spaces
         .replace(/\u00A0/g, ' ')
         // Collapse consecutive spaces into one
diff --git a/apps/readest-app/src/utils/number.ts b/apps/readest-app/src/utils/number.ts
index e06baaa7..e1ae25c5 100644
--- a/apps/readest-app/src/utils/number.ts
+++ b/apps/readest-app/src/utils/number.ts
@@ -36,15 +36,13 @@ export const localizeNumber = (num: number, language: string, isIndex = false):
 
   if (!isIndex) {
     if (isTraditional) {
-      result = result.replace(
-        /^貳$|(?<![壹貳叁肆伍陸柒捌玖])貳(?![佰仟萬億壹貳叁肆伍陸柒捌玖])/g,
-        '兩',
-      );
+      result = result
+        .replace(/^貳$/, '兩')
+        .replace(/(^|[^壹貳叁肆伍陸柒捌玖])貳([^佰仟萬億壹貳叁肆伍陸柒捌玖]|$)/g, '$1兩$2');
     } else {
-      result = result.replace(
-        /^二$|(?<![一二三四五六七八九])二(?![百千万亿一二三四五六七八九])/g,
-        '两',
-      );
+      result = result
+        .replace(/^二$/, '两')
+        .replace(/(^|[^一二三四五六七八九])二([^百千万亿一二三四五六七八九]|$)/g, '$1两$2');
     }
   }
 
diff --git a/packages/foliate-js b/packages/foliate-js
index a97db3e9..a6b6252d 160000
--- a/packages/foliate-js
+++ b/packages/foliate-js
@@ -1 +1 @@
-Subproject commit a97db3e9cf350ec0bb9ff3eb106d067f9811bf5f
+Subproject commit a6b6252d7c1fa2c30556f1ba2c69338ab1972b62