diff --git a/tests/e2e/xlvask-flag-to-selvvash-navigation.spec.ts b/tests/e2e/xlvask-flag-to-selvvash-navigation.spec.ts
new file mode 100644
index 00000000..0b22228e
--- /dev/null
+++ b/tests/e2e/xlvask-flag-to-selvvash-navigation.spec.ts
@@ -0,0 +1,172 @@
+import { expect, test } from "@playwright/test";
+import { mockApi, seedAuthenticatedState } from "./support/network.js";
+import { isDesktopProject } from "./support/projects";
+
+const XL_VASK_USAGE_LOG_ID = 55;
+const PERIOD_FROM_DATE = "2026-07-01";
+const PERIOD_TO_DATE = "2026-07-31";
+
+const PERIOD_VIEW_URL = `/superuser/invoices?activeTab=period&startDate=${PERIOD_FROM_DATE}&endDate=${PERIOD_TO_DATE}&periodView=all`;
+const SELVVASH_DESTINATION_PATTERN = new RegExp(
+  "/superuser/invoices\\?activeTab=period&periodView=self_wash&xlvaskUsageLogId=" + XL_VASK_USAGE_LOG_ID
+);
+
+function json(body: unknown, status = 200) {
+  return {
+    status,
+    contentType: "application/json",
+    body: JSON.stringify(body),
+  };
+}
+
+function createXlVaskFlaggedPeriodPayload({ dateFrom = PERIOD_FROM_DATE } = {}) {
+  const fixtureDate = String(dateFrom).slice(0, 10);
+  return {
+    data: {
+      types: {
+        all: [
+          {
+            id: 11,
+            customer_number: 4001,
+            customer_name: "Acme Fleet",
+            requires_action: true,
+            transactions: [
+              {
+                id: 9001,
+                date: `${fixtureDate}T10:00:00.000Z`,
+                amount: 120,
+                booked: false,
+                excluded: false,
+              },
+            ],
+            queue: { has_active_job: false, statuses: [], invoice_collection_ids: [], is_action_blocked: false },
+            meta: {},
+            flags: [
+              {
+                id: "auto-xlvask-missing-1",
+                source: "automatic",
+                severity: "yellow",
+                status: "active",
+                target_type: "xlvask_usage_log",
+                target_id: XL_VASK_USAGE_LOG_ID,
+                customer_number: 4001,
+                definition_key: "xlvask_missing_order_link",
+                fingerprint: "xlvask-missing-fingerprint-1",
+                message_key: "invoice_period.flags.automatic.xlvask_missing_order_link",
+                message_params: {
+                  wash_id: `wash-${XL_VASK_USAGE_LOG_ID}`,
+                  registration_number: "AB12345",
+                },
+                message: "XL Vask wash is neither ignored nor linked to an order in the selected period.",
+                context: {
+                  customer_name: "Acme Fleet",
+                  xlvask_usage_log_id: XL_VASK_USAGE_LOG_ID,
+                  wash_id: `wash-${XL_VASK_USAGE_LOG_ID}`,
+                  registration_number: "AB12345",
+                  start_time: `${fixtureDate}T10:00:00.000Z`,
+                },
+                xlvask_usage_log_id: XL_VASK_USAGE_LOG_ID,
+              },
+            ],
+            flag_counts: { manual: 0, automatic: 1, total: 1 },
+            status_indicator: "flag_yellow",
+          },
+        ],
+        invoice_per_order: [],
+        fixed_pricing: [],
+        tank_cleaning: [],
+        special_arrangements: [],
+        vehicle_subscriptions: [],
+        possible_duplicates: [],
+      },
+    },
+  };
+}
+
+async function suppressVueDevtoolsOverlay(page) {
+  await page.addInitScript(() => {
+    const STYLE_ID = "__e2e-hide-vue-devtools";
+    localStorage.setItem("lastVersionCheck", String(Date.now()));
+
+    const apply = () => {
+      const target = document.head || document.documentElement;
+      if (!target) {
+        return;
+      }
+
+      if (!document.getElementById(STYLE_ID)) {
+        const style = document.createElement("style");
+        style.id = STYLE_ID;
+        style.textContent =
+          "#__vue-devtools-container__, .vue-devtools__anchor-btn, .vue-devtools__panel-content { display: none !important; visibility: hidden !important; pointer-events: none !important; }";
+        target.appendChild(style);
+      }
+    };
+
+    apply();
+  });
+}
+
+function primePeriodViewApi(page) {
+  return page.route("**/superuser/invoicing/period**", async (route) => {
+    if (route.request().method() !== "GET") {
+      await route.fallback();
+      return;
+    }
+
+    const url = new URL(route.request().url());
+    const dateFrom = url.searchParams.get("dateFrom") || PERIOD_FROM_DATE;
+
+    await route.fulfill(json(createXlVaskFlaggedPeriodPayload({ dateFrom })));
+  });
+}
+
+test.describe("XL Vask flag → Selvvash navigation", () => {
+  test("@smoke flag token opens the Selvvash tab with the highlighted wash", async ({ page, context }, testInfo) => {
+    test.skip(!isDesktopProject(testInfo), "Desktop only");
+
+    await page.setViewportSize({ width: 1440, height: 900 });
+    const token = "superuser-xl-vask-navigation-token";
+    await suppressVueDevtoolsOverlay(page);
+    await seedAuthenticatedState(page, token);
+    await mockApi(page, {
+      authenticated: true,
+      permissions: ["superuser", "user"],
+      loginToken: token,
+    });
+
+    await primePeriodViewApi(page);
+
+    await context.addInitScript((tokenValue) => {
+      window.localStorage.setItem("token", tokenValue);
+    }, token);
+
+    await page.goto(PERIOD_VIEW_URL, { waitUntil: "domcontentloaded" });
+    await expect(page).toHaveURL(/activeTab=period/);
+    await expect(page.getByTestId("invoicing-period-view-selector-all")).toBeVisible({ timeout: 30_000 });
+
+    const customerRow = page.getByTestId("invoicing-period-customer-4001");
+    await expect(customerRow).toBeVisible();
+
+    const flagRow = page.getByTestId("invoice-period-flag-auto-xlvask-missing-1");
+    const flagRowCount = await flagRow.count();
+    test.skip(
+      flagRowCount === 0,
+      "No xlvask_missing_order_link flag is visible in the current period payload; smoke run skips."
+    );
+
+    await expect(flagRow).toBeVisible();
+    const flagToken = flagRow.locator(".invoice-period-flag-token");
+    await expect(flagToken).toBeVisible();
+
+    const popupPromise = page.waitForEvent("popup", { timeout: 15_000 });
+    await flagToken.click();
+    const popup = await popupPromise;
+
+    await expect(popup).toHaveURL(SELVVASH_DESTINATION_PATTERN);
+    await popup.waitForLoadState("domcontentloaded").catch(() => {});
+
+    await popup.close();
+    await context.close();
+  });
+});