diff --git a/.changeset/orange-lobsters-lay.md b/.changeset/orange-lobsters-lay.md
new file mode 100644
index 0000000000..0e66f00606
--- /dev/null
+++ b/.changeset/orange-lobsters-lay.md
@@ -0,0 +1,5 @@
+---
+"@react-router/dev": patch
+---
+
+fix(dev): add param to route css so it is not deduped by react
diff --git a/.github/workflows/close-no-repro-issues.yml b/.github/workflows/close-no-repro-issues.yml
index f9a6e2e45f..efc77ff396 100644
--- a/.github/workflows/close-no-repro-issues.yml
+++ b/.github/workflows/close-no-repro-issues.yml
@@ -31,7 +31,7 @@ jobs:
         uses: pnpm/action-setup@v4.1.0
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           # required for --experimental-strip-types
           node-version: 22
diff --git a/.github/workflows/deduplicate-lock-file.yml b/.github/workflows/deduplicate-lock-file.yml
index 51d6c758b4..3174fcfcbb 100644
--- a/.github/workflows/deduplicate-lock-file.yml
+++ b/.github/workflows/deduplicate-lock-file.yml
@@ -26,7 +26,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: "pnpm"
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 86ced6e59e..1e6391dfd8 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -35,7 +35,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: pnpm
diff --git a/.github/workflows/format.yml b/.github/workflows/format.yml
index 459c848d12..ff63cd21ee 100644
--- a/.github/workflows/format.yml
+++ b/.github/workflows/format.yml
@@ -25,7 +25,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: pnpm
diff --git a/.github/workflows/release-experimental.yml b/.github/workflows/release-experimental.yml
index 1b4624d7f4..373afa10ba 100644
--- a/.github/workflows/release-experimental.yml
+++ b/.github/workflows/release-experimental.yml
@@ -29,7 +29,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: "pnpm"
diff --git a/.github/workflows/release-nightly.yml b/.github/workflows/release-nightly.yml
index b394521418..be5ec510e8 100644
--- a/.github/workflows/release-nightly.yml
+++ b/.github/workflows/release-nightly.yml
@@ -40,7 +40,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: "pnpm"
diff --git a/.github/workflows/release-stage-2-alpha.yml b/.github/workflows/release-stage-2-alpha.yml
index 40157097f3..c82f906205 100644
--- a/.github/workflows/release-stage-2-alpha.yml
+++ b/.github/workflows/release-stage-2-alpha.yml
@@ -35,7 +35,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: "pnpm"
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 366c8dcc9f..b88bb74292 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -35,7 +35,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: "pnpm"
@@ -84,7 +84,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: "pnpm"
diff --git a/.github/workflows/shared-build.yml b/.github/workflows/shared-build.yml
index 345ec9c300..4a3617aa6c 100644
--- a/.github/workflows/shared-build.yml
+++ b/.github/workflows/shared-build.yml
@@ -17,7 +17,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version-file: ".nvmrc"
           cache: "pnpm"
diff --git a/.github/workflows/shared-integration.yml b/.github/workflows/shared-integration.yml
index 0454fc2cca..782507c3ac 100644
--- a/.github/workflows/shared-integration.yml
+++ b/.github/workflows/shared-integration.yml
@@ -44,7 +44,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node ${{ matrix.node }}
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version: ${{ matrix.node }}
           cache: "pnpm"
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index d510f93a25..2bf0dedbe9 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -39,7 +39,7 @@ jobs:
         uses: pnpm/action-setup@v4
 
       - name: ⎔ Setup node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version: ${{ matrix.node }}
           cache: pnpm
diff --git a/contributors.yml b/contributors.yml
index 0b1dee6722..7f5bbd347a 100644
--- a/contributors.yml
+++ b/contributors.yml
@@ -190,6 +190,7 @@
 - johnpangalos
 - jonkoops
 - joseph0926
+- joshuaellis
 - jplhomer
 - jrakotoharisoa
 - jrestall
@@ -308,6 +309,7 @@
 - pawelblaszczyk5
 - pcattori
 - penx
+- peterneave
 - petersendidit
 - phildl
 - phryneas
diff --git a/docs/api/data-routers/createHashRouter.md b/docs/api/data-routers/createHashRouter.md
index 528410ec37..307944a3fa 100644
--- a/docs/api/data-routers/createHashRouter.md
+++ b/docs/api/data-routers/createHashRouter.md
@@ -23,7 +23,7 @@ https://github.com/remix-run/react-router/blob/main/packages/react-router/lib/do
 [Reference Documentation ↗](https://api.reactrouter.com/v7/functions/react_router.createHashRouter.html)
 
 Create a new [data router](https://api.reactrouter.com/v7/interfaces/react_router.DataRouter.html) that manages the application
-path via the URL [`hash`]https://developer.mozilla.org/en-US/docs/Web/API/URL/hash).
+path via the URL [`hash`](https://developer.mozilla.org/en-US/docs/Web/API/URL/hash).
 
 ## Signature
 
diff --git a/integration/css-lazy-loading-test.ts b/integration/css-lazy-loading-test.ts
new file mode 100644
index 0000000000..852ecdc857
--- /dev/null
+++ b/integration/css-lazy-loading-test.ts
@@ -0,0 +1,183 @@
+import { test, expect } from "@playwright/test";
+
+import { PlaywrightFixture } from "./helpers/playwright-fixture.js";
+import type { Fixture, AppFixture } from "./helpers/create-fixture.js";
+import {
+  createAppFixture,
+  createFixture,
+  css,
+  js,
+} from "./helpers/create-fixture.js";
+
+let fixture: Fixture;
+let appFixture: AppFixture;
+
+test.beforeEach(async ({ context }) => {
+  await context.route(/\.data$/, async (route) => {
+    await new Promise((resolve) => setTimeout(resolve, 50));
+    route.continue();
+  });
+});
+
+test.beforeAll(async () => {
+  fixture = await createFixture({
+    files: {
+      "app/routes.ts": js`
+        import { type RouteConfig, index, route } from "@react-router/dev/routes";
+
+        export default [
+          index("routes/home.tsx"),
+          route("company", "routes/layout.tsx", [
+            route("books", "routes/books/route.tsx"),
+            route("publishers", "routes/publishers/route.tsx"),
+          ]),
+        ] satisfies RouteConfig;
+      `,
+
+      "app/components/Icon.module.css": css`
+        .icon {
+          width: 20px;
+          height: 20px;
+          background-color: green;
+        }
+      `,
+
+      "app/components/Icon.tsx": js`
+        import styles from "./Icon.module.css";
+
+        export const Icon = () => {
+          return <div data-testid="icon" className={styles.icon} />;
+        }
+      `,
+
+      "app/components/LazyIcon.tsx": js`
+        import { lazy, Suspense } from "react";
+
+        const Icon = lazy(() =>
+          import("../components/Icon").then((m) => ({ default: m.Icon }))
+        );
+
+        const LazyIcon = ({ show }: { show: boolean }) => {
+          if (!show) return null;
+
+          return (
+            <Suspense fallback={<div>Loading...</div>}>
+              <Icon />
+            </Suspense>
+          );
+        };
+
+        export { LazyIcon };
+      `,
+
+      "app/routes/home.tsx": js`
+        import { redirect } from "react-router";
+
+        export const loader = () => {
+          return redirect("/company/books");
+        };
+      `,
+
+      "app/routes/layout.tsx": js`
+        import { Link, Outlet } from "react-router";
+
+        import { LazyIcon } from "../components/LazyIcon";
+        import { useState, useEffect } from "react";
+
+        export default function Layout() {
+          const [hydrated, setHydrated] = useState(false);
+          const [show, setShow] = useState(false);
+
+          useEffect(() => {
+            setShow(true);
+          },[])
+
+          return (
+            <div style={{ border: "1px solid blue" }}>
+              <h1>Layout</h1>
+              <nav>
+                <Link to="/company/books">Books</Link>
+                <Link to="/company/publishers">Publishers</Link>
+              </nav>
+              <div>
+                <LazyIcon show={show} />
+              </div>
+              <div style={{ border: "1px solid red" }}>
+                <Outlet />
+              </div>
+            </div>
+          );
+        }
+      `,
+
+      "app/routes/books/route.tsx": js`
+        import { Icon } from "../../components/Icon";
+
+        export default function BooksRoute() {
+          return (
+            <>
+              <h1>Books</h1>
+              <div>
+                <Icon />
+              </div>
+            </>
+          );
+        }
+
+      `,
+
+      "app/routes/publishers/route.tsx": js`
+        export default function PublishersRoute() {
+          return <h1>Publishers</h1>;
+        }
+      `,
+    },
+  });
+
+  // This creates an interactive app using playwright.
+  appFixture = await createAppFixture(fixture);
+});
+
+test.afterAll(() => {
+  appFixture.close();
+});
+
+test("should preserve the CSS from the lazy loaded component even when it's in the route css manifest", async ({
+  page,
+}) => {
+  let app = new PlaywrightFixture(appFixture, page);
+  await app.goto("/");
+
+  expect(await page.getByTestId("icon").all()).toHaveLength(1);
+
+  // check the head for a link to the css that includes the word `Icon`
+  const links1 = await page.$$("link");
+  let found1 = false;
+  for (const link of links1) {
+    const href = await link.getAttribute("href");
+    if (href?.includes("Icon") && href.includes("css")) {
+      found1 = true;
+    }
+  }
+
+  expect(found1).toBe(true);
+
+  // wait for the loading to be gone before checking the lazy loaded component has resolved
+  await expect(page.getByText("Loading...")).toHaveCount(0);
+  expect(await page.getByTestId("icon").all()).toHaveLength(2);
+
+  await app.clickLink("/company/publishers");
+
+  expect(await page.getByTestId("icon").all()).toHaveLength(1);
+
+  const links2 = await page.$$("link");
+  let found2 = false;
+  for (const link of links2) {
+    const href = await link.getAttribute("href");
+    if (href?.includes("Icon") && href.includes("css")) {
+      found2 = true;
+    }
+  }
+
+  expect(found2).toBe(true);
+});
diff --git a/integration/vite-dot-server-test.ts b/integration/vite-dot-server-test.ts
index 77e749d192..6e686d6b01 100644
--- a/integration/vite-dot-server-test.ts
+++ b/integration/vite-dot-server-test.ts
@@ -146,7 +146,7 @@ test.describe("Vite / route / server-only module referenced by client", () => {
 
         `  But other route exports in 'app/routes/_index.tsx' depend on '${specifier}'.`,
 
-        "  See https://remix.run/docs/en/main/guides/vite#splitting-up-client-and-server-code",
+        "  See https://reactrouter.com/explanation/code-splitting#removal-of-server-code",
       ].forEach(expect(stderr).toMatch);
     });
   }
@@ -206,7 +206,7 @@ test.describe("Vite / non-route / server-only module referenced by client", () =
 
         `    '${specifier}' imported by 'app/reexport-server-only.ts'`,
 
-        "  See https://remix.run/docs/en/main/guides/vite#splitting-up-client-and-server-code",
+        "  See https://reactrouter.com/explanation/code-splitting#removal-of-server-code",
       ].forEach(expect(stderr).toMatch);
     });
   }
diff --git a/packages/react-router-dev/vite/plugin.ts b/packages/react-router-dev/vite/plugin.ts
index d409f808c0..a4afbd0260 100644
--- a/packages/react-router-dev/vite/plugin.ts
+++ b/packages/react-router-dev/vite/plugin.ts
@@ -394,7 +394,7 @@ const getReactRouterManifestBuildAssets = (
           : null,
         chunks
           .flatMap((e) => e.css ?? [])
-          .map((href) => `${ctx.publicPath}${href}`),
+          .map((href) => `${ctx.publicPath}${href}#route=true`),
       ]
         .flat(1)
         .filter(isNonNullable),
@@ -2084,7 +2084,7 @@ export const reactRouterVitePlugin: ReactRouterVitePlugin = () => {
               "",
               `  But other route exports in '${importerShort}' depend on '${id}'.`,
               "",
-              "  See https://remix.run/docs/en/main/guides/vite#splitting-up-client-and-server-code",
+              "  See https://reactrouter.com/explanation/code-splitting#removal-of-server-code",
               "",
             ].join("\n"),
           );
@@ -2096,7 +2096,7 @@ export const reactRouterVitePlugin: ReactRouterVitePlugin = () => {
             "",
             `    '${id}' imported by '${importerShort}'`,
             "",
-            "  See https://remix.run/docs/en/main/guides/vite#splitting-up-client-and-server-code",
+            "  See https://reactrouter.com/explanation/code-splitting#removal-of-server-code",
             "",
           ].join("\n"),
         );
diff --git a/packages/react-router-fs-routes/index.ts b/packages/react-router-fs-routes/index.ts
index a68afc85e2..11d02ffb89 100644
--- a/packages/react-router-fs-routes/index.ts
+++ b/packages/react-router-fs-routes/index.ts
@@ -12,7 +12,7 @@ import { normalizeSlashes } from "./normalizeSlashes";
 /**
  * Creates route config from the file system using a convention that matches
  * [Remix v2's route file
- * naming](https://remix.run/docs/en/v2/file-conventions/routes-files), for use
+ * naming](https://v2.remix.run/docs/file-conventions/routes), for use
  * within `routes.ts`.
  */
 export async function flatRoutes(
diff --git a/packages/react-router-node/sessions/fileStorage.ts b/packages/react-router-node/sessions/fileStorage.ts
index 3d2c30ae41..840d463a5f 100644
--- a/packages/react-router-node/sessions/fileStorage.ts
+++ b/packages/react-router-node/sessions/fileStorage.ts
@@ -26,7 +26,7 @@ interface FileSessionStorageOptions {
  * The advantage of using this instead of cookie session storage is that
  * files may contain much more data than cookies.
  *
- * @see https://remix.run/utils/sessions#createfilesessionstorage-node
+ * @see https://api.reactrouter.com/v7/functions/_react_router_node.createFileSessionStorage
  */
 export function createFileSessionStorage<Data = SessionData, FlashData = Data>({
   cookie,
diff --git a/packages/react-router-remix-routes-option-adapter/index.ts b/packages/react-router-remix-routes-option-adapter/index.ts
index 77f2582068..219b7a5780 100644
--- a/packages/react-router-remix-routes-option-adapter/index.ts
+++ b/packages/react-router-remix-routes-option-adapter/index.ts
@@ -11,7 +11,7 @@ export type { DefineRoutesFunction, DefineRouteFunction };
 
 /**
  * Adapts routes defined using [Remix's `routes` config
- * option](https://remix.run/docs/en/v2/file-conventions/vite-config#routes) to
+ * option](https://v2.remix.run/docs/file-conventions/vite-config#routes) to
  * React Router's config format, for use within `routes.ts`.
  */
 export async function remixRoutesOptionAdapter(
diff --git a/packages/react-router/lib/dom/lib.tsx b/packages/react-router/lib/dom/lib.tsx
index ecbe52374e..92cda6b050 100644
--- a/packages/react-router/lib/dom/lib.tsx
+++ b/packages/react-router/lib/dom/lib.tsx
@@ -766,7 +766,7 @@ export function createBrowserRouter(
 
 /**
  * Create a new {@link DataRouter| data router} that manages the application
- * path via the URL [`hash`]https://developer.mozilla.org/en-US/docs/Web/API/URL/hash).
+ * path via the URL [`hash`](https://developer.mozilla.org/en-US/docs/Web/API/URL/hash).
  *
  * @public
  * @category Data Routers
diff --git a/packages/react-router/lib/dom/ssr/routeModules.ts b/packages/react-router/lib/dom/ssr/routeModules.ts
index c06e8b617c..e8926d46b4 100644
--- a/packages/react-router/lib/dom/ssr/routeModules.ts
+++ b/packages/react-router/lib/dom/ssr/routeModules.ts
@@ -119,7 +119,7 @@ export type LayoutComponent = ComponentType<{
  * A function that defines `<link>` tags to be inserted into the `<head>` of
  * the document on route transitions.
  *
- * @see https://remix.run/route/meta
+ * @see https://reactrouter.com/start/framework/route-module#meta
  */
 export interface LinksFunction {
   (): LinkDescriptor[];
@@ -267,7 +267,7 @@ export type RouteComponent = ComponentType<{}>;
 /**
  * An arbitrary object that is associated with a route.
  *
- * @see https://remix.run/route/handle
+ * @see https://reactrouter.com/how-to/using-handle
  */
 export type RouteHandle = unknown;