diff --git a/background/steps/create-plus-checkout.js b/background/steps/create-plus-checkout.js
index 5ac76a5..e7e334f 100644
--- a/background/steps/create-plus-checkout.js
+++ b/background/steps/create-plus-checkout.js
@@ -16,6 +16,7 @@
       addLog: rawAddLog = async () => {},
       chrome,
       completeStepFromBackground,
+      createAutomationTab = null,
       ensureContentScriptReadyOnTabUntilStopped,
       fetch: fetchImpl = null,
       registerTab,
@@ -63,7 +64,9 @@
     }
 
     async function openFreshChatGptTabForCheckoutCreate() {
-      const tab = await chrome.tabs.create({ url: PLUS_CHECKOUT_ENTRY_URL, active: true });
+      const tab = typeof createAutomationTab === 'function'
+        ? await createAutomationTab({ url: PLUS_CHECKOUT_ENTRY_URL, active: true })
+        : await chrome.tabs.create({ url: PLUS_CHECKOUT_ENTRY_URL, active: true });
       const tabId = Number(tab?.id);
       if (!Number.isInteger(tabId)) {
         throw new Error('步骤 6：打开 ChatGPT 页面失败，无法创建订阅页。');
diff --git a/background/steps/fill-plus-checkout.js b/background/steps/fill-plus-checkout.js
index a6a5766..43748aa 100644
--- a/background/steps/fill-plus-checkout.js
+++ b/background/steps/fill-plus-checkout.js
@@ -88,6 +88,7 @@
       getTabId,
       isTabAlive,
       markCurrentRegistrationAccountUsed,
+      queryTabsInAutomationWindow = null,
       setState,
       sleepWithStop,
       waitForTabCompleteUntilStopped,
@@ -1364,13 +1365,16 @@
         return null;
       }
 
-      const activeTabs = await chrome.tabs.query({ active: true, currentWindow: true }).catch(() => []);
+      const queryTabs = typeof queryTabsInAutomationWindow === 'function'
+        ? queryTabsInAutomationWindow
+        : (queryInfo) => chrome.tabs.query(queryInfo);
+      const activeTabs = await queryTabs({ active: true, currentWindow: true }).catch(() => []);
       const activeCheckoutTab = activeTabs.find((tab) => Number.isInteger(tab?.id) && isPlusCheckoutUrl(tab.url));
       if (activeCheckoutTab) {
         return activeCheckoutTab.id;
       }
 
-      const checkoutTabs = await chrome.tabs.query({ url: 'https://chatgpt.com/checkout/*' }).catch(() => []);
+      const checkoutTabs = await queryTabs({ url: 'https://chatgpt.com/checkout/*' }).catch(() => []);
       const checkoutTab = checkoutTabs.find((tab) => Number.isInteger(tab?.id) && isPlusCheckoutUrl(tab.url));
       return checkoutTab?.id || null;
     }
diff --git a/background/steps/gopay-approve.js b/background/steps/gopay-approve.js
index 4f3d085..5505679 100644
--- a/background/steps/gopay-approve.js
+++ b/background/steps/gopay-approve.js
@@ -21,6 +21,7 @@
       ensureContentScriptReadyOnTabUntilStopped,
       getTabId,
       isTabAlive,
+      queryTabsInAutomationWindow = null,
       registerTab,
       sendTabMessageUntilStopped,
       setState,
@@ -110,7 +111,10 @@
       if (!chrome?.tabs?.query) {
         return 0;
       }
-      const tabs = await chrome.tabs.query({}).catch(() => []);
+      const queryTabs = typeof queryTabsInAutomationWindow === 'function'
+        ? queryTabsInAutomationWindow
+        : (queryInfo) => chrome.tabs.query(queryInfo);
+      const tabs = await queryTabs({}).catch(() => []);
       const candidates = (Array.isArray(tabs) ? tabs : [])
         .filter((tab) => Number.isInteger(tab?.id) && predicate(tab.url || ''));
       if (!candidates.length) {
diff --git a/background/steps/gopay-manual-confirm.js b/background/steps/gopay-manual-confirm.js
index f33724c..0fe4a7a 100644
--- a/background/steps/gopay-manual-confirm.js
+++ b/background/steps/gopay-manual-confirm.js
@@ -10,6 +10,7 @@
       addLog,
       broadcastDataUpdate,
       chrome,
+      createAutomationTab = null,
       getTabId,
       isTabAlive,
       registerTab,
@@ -48,7 +49,9 @@
         throw new Error('步骤 7：无法自动重新打开 GoPay 订阅页。');
       }
 
-      const tab = await chrome.tabs.create({ url: checkoutUrl, active: true });
+      const tab = typeof createAutomationTab === 'function'
+        ? await createAutomationTab({ url: checkoutUrl, active: true })
+        : await chrome.tabs.create({ url: checkoutUrl, active: true });
       const tabId = Number(tab?.id) || 0;
       if (!tabId) {
         throw new Error('步骤 7：重新打开 GoPay 订阅页失败。');
diff --git a/background/steps/paypal-approve.js b/background/steps/paypal-approve.js
index f385599..64c518f 100644
--- a/background/steps/paypal-approve.js
+++ b/background/steps/paypal-approve.js
@@ -15,6 +15,7 @@
       ensureContentScriptReadyOnTabUntilStopped,
       getTabId,
       isTabAlive,
+      queryTabsInAutomationWindow = null,
       sendTabMessageUntilStopped,
       setState,
       sleepWithStop,
@@ -48,7 +49,10 @@
         return 0;
       }
 
-      const tabs = await chrome.tabs.query({}).catch(() => []);
+      const queryTabs = typeof queryTabsInAutomationWindow === 'function'
+        ? queryTabsInAutomationWindow
+        : (queryInfo) => chrome.tabs.query(queryInfo);
+      const tabs = await queryTabs({}).catch(() => []);
       const candidates = (Array.isArray(tabs) ? tabs : [])
         .filter((tab) => Number.isInteger(tab?.id) && isPayPalUrl(tab.url || ''));
       if (!candidates.length) {
diff --git a/tests/plus-checkout-billing-tab-resolution.test.js b/tests/plus-checkout-billing-tab-resolution.test.js
index 648731e..c279698 100644
--- a/tests/plus-checkout-billing-tab-resolution.test.js
+++ b/tests/plus-checkout-billing-tab-resolution.test.js
@@ -82,6 +82,7 @@ function createExecutorHarness({
   fetchImpl = null,
   getAddressSeedForCountry = () => createAddressSeed(),
   getState = null,
+  queryTabsInAutomationWindow = null,
   markCurrentRegistrationAccountUsed = async () => {},
   probeIpProxyExit = null,
   onSetState = null,
@@ -161,6 +162,7 @@ function createExecutorHarness({
     getTabId: async () => null,
     isTabAlive: async () => false,
     markCurrentRegistrationAccountUsed,
+    ...(typeof queryTabsInAutomationWindow === 'function' ? { queryTabsInAutomationWindow } : {}),
     setState: async (updates) => {
       events.states.push(updates);
       if (typeof onSetState === 'function') {
@@ -240,6 +242,38 @@ test('Plus checkout billing uses the current checkout tab when step 6 did not re
   assert.equal(events.logs.some((entry) => /当前已在 Plus Checkout 页面/.test(entry.message)), true);
 });
 
+test('Plus checkout billing searches checkout tabs inside the locked automation window', async () => {
+  const queries = [];
+  const { checkoutTab, executor } = createExecutorHarness({
+    frames: [{ frameId: 0, url: 'https://chatgpt.com/checkout/openai_ie/cs_test' }],
+    queryTabsInAutomationWindow: async (queryInfo) => {
+      queries.push(queryInfo);
+      if (queryInfo?.active) {
+        return [];
+      }
+      if (queryInfo?.url === 'https://chatgpt.com/checkout/*') {
+        return [checkoutTab];
+      }
+      return [];
+    },
+    stateByFrame: {
+      0: {
+        hasPayPal: true,
+        paypalCandidates: [{ tag: 'button', text: 'PayPal' }],
+        billingFieldsVisible: true,
+        hasSubscribeButton: true,
+      },
+    },
+  });
+
+  await executor.executePlusCheckoutBilling({});
+
+  assert.deepEqual(queries, [
+    { active: true, currentWindow: true },
+    { url: 'https://chatgpt.com/checkout/*' },
+  ]);
+});
+
 test('Plus checkout billing sends the billing command to the iframe that contains PayPal', async () => {
   const { events, executor } = createExecutorHarness({
     frames: [