diff --git a/.changeset/pwa-https-cold-start-hotfix.md b/.changeset/pwa-https-cold-start-hotfix.md
new file mode 100644
index 000000000..e024dca25
--- /dev/null
+++ b/.changeset/pwa-https-cold-start-hotfix.md
@@ -0,0 +1,5 @@
+---
+'@app/ratewise': patch
+---
+
+修復 PWA 冷啟動時 Chrome 顯示「此連結並不安全」警告：manifest 改為絕對 HTTPS scope，且 Service Worker 不再快取舊版 manifest。
diff --git a/apps/ratewise/public/manifest.webmanifest b/apps/ratewise/public/manifest.webmanifest
index 90f7c30ab..63336ef2d 100644
--- a/apps/ratewise/public/manifest.webmanifest
+++ b/apps/ratewise/public/manifest.webmanifest
@@ -5,7 +5,7 @@
   "theme_color": "#8B5CF6",
   "background_color": "#E8ECF4",
   "display": "standalone",
-  "scope": "/ratewise/",
+  "scope": "https://app.haotool.org/ratewise/",
   "start_url": "https://app.haotool.org/ratewise/",
   "id": "/ratewise/",
   "orientation": "portrait-primary",
diff --git a/apps/ratewise/scripts/generate-manifest.mjs b/apps/ratewise/scripts/generate-manifest.mjs
index 4e425fbd8..6fe2fe52f 100644
--- a/apps/ratewise/scripts/generate-manifest.mjs
+++ b/apps/ratewise/scripts/generate-manifest.mjs
@@ -24,9 +24,9 @@ const manifest = {
   theme_color: '#8B5CF6',
   background_color: '#E8ECF4',
   display: 'standalone',
-  scope: '/ratewise/',
-  // 絕對 HTTPS start_url：避免獨立 PWA partition + Chrome HTTPS-First 在啟動時以 http 語意解析。
-  // id/scope 維持相對（id 變更會被視為新 PWA 身分，破壞既有安裝更新連續性）。
+  // 絕對 HTTPS scope/start_url：避免獨立 PWA partition + Chrome HTTPS-First 在啟動時以 http 語意解析。
+  // id 維持相對（id 變更會被視為新 PWA 身分，破壞既有安裝更新連續性）。
+  scope: APP_INFO.siteUrl,
   start_url: APP_INFO.siteUrl,
   id: '/ratewise/',
   orientation: 'portrait-primary',
diff --git a/apps/ratewise/src/__tests__/sw.test.ts b/apps/ratewise/src/__tests__/sw.test.ts
index 4151362e5..616faad01 100644
--- a/apps/ratewise/src/__tests__/sw.test.ts
+++ b/apps/ratewise/src/__tests__/sw.test.ts
@@ -242,6 +242,17 @@ describe('Service Worker Cache Strategies', () => {
     expect(sourceCode).toContain('new NetworkOnly(');
   });
 
+  it('should fetch manifest.webmanifest with NetworkOnly to avoid stale relative start_url', async () => {
+    const fs = await import('node:fs/promises');
+    const path = await import('node:path');
+
+    const swPath = path.resolve(__dirname, '../sw.ts');
+    const sourceCode = await fs.readFile(swPath, 'utf-8');
+
+    expect(sourceCode).toContain("url.pathname.endsWith('.webmanifest')");
+    expect(sourceCode).not.toContain('.(webmanifest|txt|xml)$');
+  });
+
   // 🔴 RED: JS/CSS 應使用 CacheFirst（Vite hash-based filenames 是 immutable）
   it('should use CacheFirst for JS/CSS static resources (hash-based filenames are immutable)', async () => {
     const fs = await import('node:fs/promises');
diff --git a/apps/ratewise/src/config/__tests__/build-scripts.test.ts b/apps/ratewise/src/config/__tests__/build-scripts.test.ts
index b18add3d0..07d247801 100644
--- a/apps/ratewise/src/config/__tests__/build-scripts.test.ts
+++ b/apps/ratewise/src/config/__tests__/build-scripts.test.ts
@@ -260,6 +260,21 @@ describe('ratewise build scripts', () => {
     expect(manifestGenerator).not.toContain("name: 'HaoRate 匯率好工具'");
   });
 
+  it('should keep PWA manifest scope and start_url on absolute HTTPS SSOT', async () => {
+    const manifestGenerator = await readManifestGenerator();
+    const manifestPath = path.resolve(__dirname, '../../../public/manifest.webmanifest');
+    const manifest = JSON.parse(await readFile(manifestPath, 'utf-8')) as {
+      scope: string;
+      start_url: string;
+    };
+
+    expect(manifestGenerator).toContain('scope: APP_INFO.siteUrl');
+    expect(manifestGenerator).toContain('start_url: APP_INFO.siteUrl');
+    expect(manifest.scope).toMatch(/^https:\/\//);
+    expect(manifest.start_url).toMatch(/^https:\/\//);
+    expect(manifest.scope).toBe(manifest.start_url);
+  });
+
   it('should not force React ecosystem packages into manual chunks', async () => {
     const viteConfig = await readViteConfig();
     expect(viteConfig).not.toContain(
diff --git a/apps/ratewise/src/sw.ts b/apps/ratewise/src/sw.ts
index 22c4261d7..4e1149f21 100644
--- a/apps/ratewise/src/sw.ts
+++ b/apps/ratewise/src/sw.ts
@@ -457,9 +457,12 @@ registerRoute(
   }),
 );
 
-// manifest / SEO 文字檔案：StaleWhileRevalidate，7 天。
+// manifest 必須 NetworkOnly：SWR 快取會回傳舊版相對 start_url，觸發冷啟動 HTTPS-First 警告。
+registerRoute(({ url }: { url: URL }) => url.pathname.endsWith('.webmanifest'), new NetworkOnly());
+
+// SEO 文字/XML：StaleWhileRevalidate，7 天。
 registerRoute(
-  ({ url }: { url: URL }) => /\.(webmanifest|txt|xml)$/.test(url.pathname),
+  ({ url }: { url: URL }) => /\.(txt|xml)$/.test(url.pathname),
   new StaleWhileRevalidate({
     cacheName: 'seo-files-cache',
     plugins: [
diff --git a/docs/dev/002_development_reward_penalty_log.md b/docs/dev/002_development_reward_penalty_log.md
index bc38b5da5..a855d3447 100644
--- a/docs/dev/002_development_reward_penalty_log.md
+++ b/docs/dev/002_development_reward_penalty_log.md
@@ -2,7 +2,7 @@
 
 > 版本：outline-v2-ultra
 > 原則：每筆只保留日期、ID、原因、解法。
-> 本次分數變化：+1（reward 1、penalty 0、neutral 0）｜累計總分：+79
+> 本次分數變化：+1（reward 1、penalty 0、neutral 0）｜累計總分：+80
 
 ## 新增模板（4 行）
 
@@ -13,6 +13,11 @@
 
 ## 條目（新→舊）
 
+- 日期：2026-06-28
+- ID：reward-pwa-https-cold-start-manifest-regression
+- 原因：#447 已改絕對 HTTPS start_url，但 SW seo-files-cache 以 SWR 快取舊 manifest（相對 start_url），冷啟動仍觸發 HTTPS-First 警告
+- 解法：manifest.webmanifest 改 NetworkOnly、scope 同步絕對 HTTPS SSOT，並補防回歸測試
+
 - 日期：2026-06-28
 - ID：reward-threads-barcelona-inapp-ua
 - 原因：Threads 2024+ 內建瀏覽器 UA 改用 Barcelona 代號，僅匹配 Threads 字串時 PWA 安裝指引與右上角動畫不顯示