diff --git a/src/pages/install/context_fallback.test.ts b/src/pages/install/context_fallback.test.ts
new file mode 100644
index 000000000..4d43cb9ef
--- /dev/null
+++ b/src/pages/install/context_fallback.test.ts
@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+import { DocumentationSite } from "@App/app/const";
+import { getIncompleteContextFallbackUrl } from "./context_fallback";
+
+describe("getIncompleteContextFallbackUrl", () => {
+  it("扩展 API 不完整的 ?url= 安装页转到文档站安装中间页，脚本地址原样带上（含其自身的查询串）", () => {
+    const scriptUrl = "https://example.com/a.user.js?v=1&lang=zh";
+    expect(getIncompleteContextFallbackUrl(`?url=${scriptUrl}`, false)).toBe(
+      `${DocumentationSite}/docs/script_installation/#url=${scriptUrl}`
+    );
+  });
+
+  it("扩展 API 完整时不转跳，正常浏览器照常在本页安装", () => {
+    expect(getIncompleteContextFallbackUrl("?url=https://example.com/a.user.js", true)).toBeUndefined();
+  });
+
+  it("没有 ?url= 的入口（如 SW 新建的 ?uuid=）不转跳", () => {
+    expect(getIncompleteContextFallbackUrl("?uuid=8f3c2a10-0000-4000-8000-000000000000", false)).toBeUndefined();
+  });
+});
diff --git a/src/pages/install/context_fallback.ts b/src/pages/install/context_fallback.ts
new file mode 100644
index 000000000..544482eda
--- /dev/null
+++ b/src/pages/install/context_fallback.ts
@@ -0,0 +1,18 @@
+import { DocumentationSite } from "@App/app/const";
+
+/**
+ * 浏览器兼容处理（#1816）：360 X 中，网页以 noopener 新开的标签被 DNR 重定向到安装页后，页面只拿到
+ * 不完整的扩展 API（chrome.tabs / chrome.permissions 缺失，读 chrome.storage 报
+ * "Invalid context type provided."）。浏览器为何这样分类尚未确认，在本页刷新或原标签重新导航都恢复不了，
+ * 由 SW 用 tabs.create 新开的安装页才正常。
+ *
+ * 因此这种上下文改为转到文档站的安装中间页：SW 的 webNavigation 监听会接住这次导航，备好脚本后新开
+ * `?uuid=` 安装页。只有 DNR 产生的 `?url=` 入口会转跳，SW 新建的入口不会再落回这里，不会循环。
+ * `url=` 之后的整段原样转交，与安装页读取 `?url=` 的方式一致，脚本地址自带的查询串不会被截断。
+ */
+export function getIncompleteContextFallbackUrl(search: string, hasTabsApi: boolean): string | undefined {
+  if (hasTabsApi) return undefined;
+  const urlIdx = search.indexOf("url=");
+  if (urlIdx === -1) return undefined;
+  return `${DocumentationSite}/docs/script_installation/#url=${search.slice(urlIdx + 4)}`;
+}
diff --git a/src/pages/install/main.tsx b/src/pages/install/main.tsx
index 38bc39401..acc25275f 100644
--- a/src/pages/install/main.tsx
+++ b/src/pages/install/main.tsx
@@ -6,6 +6,7 @@ import { message } from "../store/global.ts";
 import MessageWriter from "@App/app/logger/message_writer.ts";
 import { ThemeProvider } from "../components/theme-provider.tsx";
 import { Toaster } from "../components/ui/sonner.tsx";
+import { getIncompleteContextFallbackUrl } from "./context_fallback.ts";
 import "@App/index.css";
 
 // 初始化日志组件
@@ -23,6 +24,11 @@ const Root = (
   </ThemeProvider>
 );
 
-ReactDOM.createRoot(document.getElementById("root") as HTMLElement).render(
-  process.env.NODE_ENV === "development" ? <React.StrictMode>{Root}</React.StrictMode> : Root
-);
+const fallbackUrl = getIncompleteContextFallbackUrl(location.search, typeof chrome.tabs !== "undefined");
+if (fallbackUrl) {
+  location.replace(fallbackUrl);
+} else {
+  ReactDOM.createRoot(document.getElementById("root") as HTMLElement).render(
+    process.env.NODE_ENV === "development" ? <React.StrictMode>{Root}</React.StrictMode> : Root
+  );
+}