diff --git a/src/preload/index.test.ts b/src/preload/index.test.ts
index b3b54126b..cf3d3c959 100644
--- a/src/preload/index.test.ts
+++ b/src/preload/index.test.ts
@@ -108,23 +108,18 @@ describe('preload/index', () => {
   });
 
   it('app.version returns dev in development', async () => {
-    const originalEnv = process.env.NODE_ENV;
-    process.env.NODE_ENV = 'development';
+    vi.stubEnv('NODE_ENV', 'development');
     const api = getExposedApi();
 
     await expect(api.app.version()).resolves.toBe('dev');
-
-    process.env.NODE_ENV = originalEnv;
   });
 
   it('app.version prefixes production version', async () => {
-    const originalEnv = process.env.NODE_ENV;
-    process.env.NODE_ENV = 'production';
+    vi.stubEnv('NODE_ENV', 'production');
     invokeMainEventMock.mockResolvedValueOnce('1.2.3');
     const api = getExposedApi();
 
     await expect(api.app.version()).resolves.toBe('v1.2.3');
-    process.env.NODE_ENV = originalEnv;
   });
 
   it('raiseNativeNotification without url calls app.show', async () => {
diff --git a/src/renderer/__helpers__/test-utils.tsx b/src/renderer/__helpers__/test-utils.tsx
index 0cf7bca4c..9b0d08544 100644
--- a/src/renderer/__helpers__/test-utils.tsx
+++ b/src/renderer/__helpers__/test-utils.tsx
@@ -4,7 +4,7 @@ import { MemoryRouter } from 'react-router-dom';
 
 import { mockAuth, mockSettings } from '../__mocks__/state-mocks';
 
-import { AppContext, type AppContextState } from '../context/App';
+import { AppContext, type AppContextState } from '../context/context';
 import { type FiltersStore, useFiltersStore } from '../stores';
 
 export { navigateMock } from './vitest.setup';
diff --git a/src/renderer/__helpers__/vitest.setup.ts b/src/renderer/__helpers__/vitest.setup.ts
index 0ea8e1574..4589132c4 100644
--- a/src/renderer/__helpers__/vitest.setup.ts
+++ b/src/renderer/__helpers__/vitest.setup.ts
@@ -15,54 +15,82 @@ vi.mock('../utils/core/random', () => ({
   randomElement: vi.fn((arr: unknown[]) => arr[0]),
 }));
 
-// Sets timezone to UTC for consistent date/time in tests and snapshots
-process.env.TZ = 'UTC';
+function getRequestTarget(input: RequestInfo | URL): string {
+  if (typeof input === 'string') {
+    return input;
+  }
+
+  if (input instanceof URL) {
+    return input.href;
+  }
+
+  if (typeof Request !== 'undefined' && input instanceof Request) {
+    return input.url;
+  }
+
+  return String(input);
+}
+
+function createGitifyBridgeApi(): Window['gitify'] {
+  return {
+    app: {
+      version: vi.fn().mockResolvedValue('v0.0.1'),
+      hide: vi.fn(),
+      quit: vi.fn(),
+      show: vi.fn(),
+    },
+    twemojiDirectory: vi.fn().mockResolvedValue('/mock/images/assets'),
+    openExternalLink: vi.fn(),
+    decryptValue: vi.fn().mockResolvedValue({ token: 'decrypted' }),
+    encryptValue: vi.fn().mockResolvedValue('encrypted'),
+    platform: {
+      isLinux: vi.fn().mockReturnValue(false),
+      isMacOS: vi.fn().mockReturnValue(true),
+      isWindows: vi.fn().mockReturnValue(false),
+    },
+    zoom: {
+      getLevel: vi.fn(),
+      setLevel: vi.fn(),
+    },
+    tray: {
+      updateColor: vi.fn(),
+      updateTitle: vi.fn(),
+      useAlternateIdleIcon: vi.fn(),
+      useUnreadActiveIcon: vi.fn(),
+    },
+    notificationSoundPath: vi.fn(),
+    onAuthCallback: vi.fn(),
+    onResetApp: vi.fn(),
+    setAutoLaunch: vi.fn(),
+    setKeepWindowOnBlur: vi.fn(),
+    applyKeyboardShortcut: vi.fn().mockResolvedValue({ success: true }),
+    raiseNativeNotification: vi.fn(),
+  };
+}
+
+window.gitify = createGitifyBridgeApi();
 
 /**
  * Reset stores
  */
 beforeEach(() => {
+  vi.stubEnv('TZ', 'UTC');
+  vi.stubGlobal(
+    'fetch',
+    vi.fn(async (input: RequestInfo | URL) => {
+      throw new Error(
+        `Unexpected network request in test: ${getRequestTarget(input)}. Mock the network boundary explicitly.`,
+      );
+    }),
+  );
   useFiltersStore.getState().reset();
   navigateMock.mockReset();
+  window.gitify = createGitifyBridgeApi();
 });
 
-/**
- * Gitify context bridge API
- */
-window.gitify = {
-  app: {
-    version: vi.fn().mockResolvedValue('v0.0.1'),
-    hide: vi.fn(),
-    quit: vi.fn(),
-    show: vi.fn(),
-  },
-  twemojiDirectory: vi.fn().mockResolvedValue('/mock/images/assets'),
-  openExternalLink: vi.fn(),
-  decryptValue: vi.fn().mockResolvedValue({ token: 'decrypted' }),
-  encryptValue: vi.fn().mockResolvedValue('encrypted'),
-  platform: {
-    isLinux: vi.fn().mockReturnValue(false),
-    isMacOS: vi.fn().mockReturnValue(true),
-    isWindows: vi.fn().mockReturnValue(false),
-  },
-  zoom: {
-    getLevel: vi.fn(),
-    setLevel: vi.fn(),
-  },
-  tray: {
-    updateColor: vi.fn(),
-    updateTitle: vi.fn(),
-    useAlternateIdleIcon: vi.fn(),
-    useUnreadActiveIcon: vi.fn(),
-  },
-  notificationSoundPath: vi.fn(),
-  onAuthCallback: vi.fn(),
-  onResetApp: vi.fn(),
-  setAutoLaunch: vi.fn(),
-  setKeepWindowOnBlur: vi.fn(),
-  applyKeyboardShortcut: vi.fn().mockResolvedValue({ success: true }),
-  raiseNativeNotification: vi.fn(),
-};
+afterEach(() => {
+  vi.useRealTimers();
+});
 
 // Mock clipboard API
 Object.defineProperty(navigator, 'clipboard', {
diff --git a/src/renderer/components/Sidebar.test.tsx b/src/renderer/components/Sidebar.test.tsx
index 56e16f50a..8a13d642b 100644
--- a/src/renderer/components/Sidebar.test.tsx
+++ b/src/renderer/components/Sidebar.test.tsx
@@ -2,7 +2,6 @@ import { screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 
 import { navigateMock, renderWithProviders } from '../__helpers__/test-utils';
-import { mockMultipleAccountNotifications } from '../__mocks__/notifications-mocks';
 import { mockSettings } from '../__mocks__/state-mocks';
 
 import * as comms from '../utils/system/comms';
@@ -60,7 +59,9 @@ describe('renderer/components/Sidebar.tsx', () => {
 
     it('renders correct icon when there are notifications', () => {
       renderWithProviders(<Sidebar />, {
-        notifications: mockMultipleAccountNotifications,
+        notificationCount: 2,
+        hasNotifications: true,
+        hasUnreadNotifications: false,
       });
 
       expect(screen.getByTestId('sidebar-notifications')).toMatchSnapshot();
@@ -132,9 +133,7 @@ describe('renderer/components/Sidebar.tsx', () => {
 
   describe('quick links', () => {
     it('opens my github issues page', async () => {
-      renderWithProviders(<Sidebar />, {
-        notifications: mockMultipleAccountNotifications,
-      });
+      renderWithProviders(<Sidebar />);
 
       await userEvent.click(screen.getByTestId('sidebar-my-issues'));
 
@@ -143,9 +142,7 @@ describe('renderer/components/Sidebar.tsx', () => {
     });
 
     it('opens my github pull requests page', async () => {
-      renderWithProviders(<Sidebar />, {
-        notifications: mockMultipleAccountNotifications,
-      });
+      renderWithProviders(<Sidebar />);
 
       await userEvent.click(screen.getByTestId('sidebar-my-pull-requests'));
 
diff --git a/src/renderer/components/settings/SettingsReset.test.tsx b/src/renderer/components/settings/SettingsReset.test.tsx
index 0b8250028..74bc4f12b 100644
--- a/src/renderer/components/settings/SettingsReset.test.tsx
+++ b/src/renderer/components/settings/SettingsReset.test.tsx
@@ -12,7 +12,10 @@ describe('renderer/components/settings/SettingsReset.tsx', () => {
   it('should reset default settings when `OK`', async () => {
     const rendererLogInfoSpy = vi.spyOn(logger, 'rendererLogInfo').mockImplementation(vi.fn());
 
-    globalThis.confirm = vi.fn(() => true); // always click 'OK'
+    vi.stubGlobal(
+      'confirm',
+      vi.fn(() => true),
+    ); // always click 'OK'
 
     await act(async () => {
       renderWithProviders(<SettingsReset />, {
@@ -28,7 +31,10 @@ describe('renderer/components/settings/SettingsReset.tsx', () => {
   });
 
   it('should skip reset default settings when `cancelled`', async () => {
-    globalThis.confirm = vi.fn(() => false); // always click 'cancel'
+    vi.stubGlobal(
+      'confirm',
+      vi.fn(() => false),
+    ); // always click 'cancel'
 
     await act(async () => {
       renderWithProviders(<SettingsReset />, {
diff --git a/src/renderer/context/App.test.tsx b/src/renderer/context/App.test.tsx
index 7ad8420e6..0a076d5cf 100644
--- a/src/renderer/context/App.test.tsx
+++ b/src/renderer/context/App.test.tsx
@@ -19,7 +19,8 @@ import { getAdapter } from '../utils/forges/registry';
 import * as notifications from '../utils/notifications/notifications';
 import * as comms from '../utils/system/comms';
 import * as tray from '../utils/system/tray';
-import { type AppContextState, AppProvider } from './App';
+import { AppProvider } from './App';
+import { type AppContextState } from './context';
 import { defaultSettings } from './defaults';
 
 vi.mock('../hooks/useNotifications');
diff --git a/src/renderer/context/App.tsx b/src/renderer/context/App.tsx
index 8c13f0dd3..f9f5ce4ff 100644
--- a/src/renderer/context/App.tsx
+++ b/src/renderer/context/App.tsx
@@ -1,12 +1,4 @@
-import {
-  createContext,
-  type ReactNode,
-  useCallback,
-  useEffect,
-  useMemo,
-  useRef,
-  useState,
-} from 'react';
+import { type ReactNode, useCallback, useEffect, useMemo, useRef, useState } from 'react';
 
 import { useTheme } from '@primer/react';
 
@@ -19,15 +11,12 @@ import { useFiltersStore } from '../stores';
 
 import type {
   Account,
-  AccountNotifications,
   AuthState,
   Forge,
-  GitifyError,
   GitifyNotification,
   Hostname,
   SettingsState,
   SettingsValue,
-  Status,
   Token,
 } from '../types';
 import { FetchType } from '../types';
@@ -66,6 +55,7 @@ import {
   mapThemeModeToColorScheme,
 } from '../utils/ui/theme';
 import { zoomLevelToPercentage, zoomPercentageToLevel } from '../utils/ui/zoom';
+import { AppContext, type AppContextState } from './context';
 import { defaultAuth, defaultSettings } from './defaults';
 
 /**
@@ -96,47 +86,6 @@ function migrateLegacyAuthState(auth: AuthState): AuthState {
   };
 }
 
-export interface AppContextState {
-  auth: AuthState;
-  isLoggedIn: boolean;
-  loginWithDeviceFlowStart: (
-    forge: Forge,
-    hostname?: Hostname,
-    scopes?: string[],
-  ) => Promise<DeviceFlowSession>;
-  loginWithDeviceFlowPoll: (forge: Forge, session: DeviceFlowSession) => Promise<Token | null>;
-  loginWithDeviceFlowComplete: (forge: Forge, token: Token, hostname: Hostname) => Promise<void>;
-  loginWithOAuthApp: (forge: Forge, data: LoginOAuthWebOptions) => Promise<void>;
-  loginWithPersonalAccessToken: (data: LoginPersonalAccessTokenOptions) => Promise<void>;
-  logoutFromAccount: (account: Account) => Promise<void>;
-
-  status: Status;
-  globalError: GitifyError | undefined;
-
-  notifications: AccountNotifications[];
-  notificationCount: number;
-  unreadNotificationCount: number;
-  hasNotifications: boolean;
-  hasUnreadNotifications: boolean;
-
-  fetchNotifications: () => Promise<void>;
-  removeAccountNotifications: (account: Account) => Promise<void>;
-
-  markNotificationsAsRead: (notifications: GitifyNotification[]) => Promise<void>;
-  markNotificationsAsDone: (notifications: GitifyNotification[]) => Promise<void>;
-  unsubscribeNotification: (notification: GitifyNotification) => Promise<void>;
-
-  settings: SettingsState;
-  resetSettings: () => void;
-  updateSetting: (name: keyof SettingsState, value: SettingsValue) => void;
-
-  /** Shown when the OS could not register the chosen global shortcut. */
-  shortcutRegistrationError: string | null;
-  clearShortcutRegistrationError: () => void;
-}
-
-export const AppContext = createContext<Partial<AppContextState> | undefined>(undefined);
-
 export const AppProvider = ({ children }: { children: ReactNode }) => {
   const existingState = loadState();
 
diff --git a/src/renderer/context/context.ts b/src/renderer/context/context.ts
new file mode 100644
index 000000000..1ac2b80e7
--- /dev/null
+++ b/src/renderer/context/context.ts
@@ -0,0 +1,60 @@
+import { createContext } from 'react';
+
+import type {
+  Account,
+  AccountNotifications,
+  AuthState,
+  Forge,
+  GitifyError,
+  GitifyNotification,
+  Hostname,
+  SettingsState,
+  SettingsValue,
+  Status,
+  Token,
+} from '../types';
+import type {
+  DeviceFlowSession,
+  LoginOAuthWebOptions,
+  LoginPersonalAccessTokenOptions,
+} from '../utils/auth/types';
+
+export interface AppContextState {
+  auth: AuthState;
+  isLoggedIn: boolean;
+  loginWithDeviceFlowStart: (
+    forge: Forge,
+    hostname?: Hostname,
+    scopes?: string[],
+  ) => Promise<DeviceFlowSession>;
+  loginWithDeviceFlowPoll: (forge: Forge, session: DeviceFlowSession) => Promise<Token | null>;
+  loginWithDeviceFlowComplete: (forge: Forge, token: Token, hostname: Hostname) => Promise<void>;
+  loginWithOAuthApp: (forge: Forge, data: LoginOAuthWebOptions) => Promise<void>;
+  loginWithPersonalAccessToken: (data: LoginPersonalAccessTokenOptions) => Promise<void>;
+  logoutFromAccount: (account: Account) => Promise<void>;
+
+  status: Status;
+  globalError: GitifyError | undefined;
+
+  notifications: AccountNotifications[];
+  notificationCount: number;
+  unreadNotificationCount: number;
+  hasNotifications: boolean;
+  hasUnreadNotifications: boolean;
+
+  fetchNotifications: () => Promise<void>;
+  removeAccountNotifications: (account: Account) => Promise<void>;
+
+  markNotificationsAsRead: (notifications: GitifyNotification[]) => Promise<void>;
+  markNotificationsAsDone: (notifications: GitifyNotification[]) => Promise<void>;
+  unsubscribeNotification: (notification: GitifyNotification) => Promise<void>;
+
+  settings: SettingsState;
+  resetSettings: () => void;
+  updateSetting: (name: keyof SettingsState, value: SettingsValue) => void;
+
+  shortcutRegistrationError: string | null;
+  clearShortcutRegistrationError: () => void;
+}
+
+export const AppContext = createContext<Partial<AppContextState> | undefined>(undefined);
diff --git a/src/renderer/hooks/useAppContext.ts b/src/renderer/hooks/useAppContext.ts
index e85db920a..207aca93e 100644
--- a/src/renderer/hooks/useAppContext.ts
+++ b/src/renderer/hooks/useAppContext.ts
@@ -1,6 +1,6 @@
 import { useContext } from 'react';
 
-import { AppContext, type AppContextState } from '../context/App';
+import { AppContext, type AppContextState } from '../context/context';
 
 /**
  * Custom hook that provides type-safe access to AppContext.
diff --git a/src/renderer/routes/LoginWithDeviceFlow.test.tsx b/src/renderer/routes/LoginWithDeviceFlow.test.tsx
index 48f8b0a71..435f55d24 100644
--- a/src/renderer/routes/LoginWithDeviceFlow.test.tsx
+++ b/src/renderer/routes/LoginWithDeviceFlow.test.tsx
@@ -3,6 +3,7 @@ import userEvent from '@testing-library/user-event';
 
 import { navigateMock, renderWithProviders } from '../__helpers__/test-utils';
 
+import * as logger from '../utils/core/logger';
 import * as comms from '../utils/system/comms';
 import { LoginWithDeviceFlowRoute } from './LoginWithDeviceFlow';
 
@@ -117,6 +118,7 @@ describe('renderer/routes/LoginWithDeviceFlow.tsx', () => {
   });
 
   it('should handle device flow errors during initialization', async () => {
+    const rendererLogErrorSpy = vi.spyOn(logger, 'rendererLogError').mockImplementation(vi.fn());
     const loginWithDeviceFlowStartMock = vi.fn().mockRejectedValueOnce(new Error('Network error'));
 
     renderWithProviders(<LoginWithDeviceFlowRoute />, {
@@ -126,6 +128,7 @@ describe('renderer/routes/LoginWithDeviceFlow.tsx', () => {
     await userEvent.click(screen.getByTestId('device-scope-full'));
 
     await screen.findByText(/Failed to start authentication/);
+    expect(rendererLogErrorSpy).toHaveBeenCalledTimes(1);
   });
 
   it('should navigate back on cancel from scope choice', async () => {
diff --git a/src/renderer/utils/forges/gitea/client.test.ts b/src/renderer/utils/forges/gitea/client.test.ts
index 0297cfa6f..896380e7e 100644
--- a/src/renderer/utils/forges/gitea/client.test.ts
+++ b/src/renderer/utils/forges/gitea/client.test.ts
@@ -12,12 +12,7 @@ import {
 } from './client';
 
 describe('renderer/utils/forges/gitea/client.ts', () => {
-  const fetchSpy = vi.spyOn(globalThis, 'fetch');
-
-  beforeEach(() => {
-    fetchSpy.mockReset();
-    vi.spyOn(comms, 'decryptValue').mockResolvedValue({ token: 'decrypted' });
-  });
+  const fetchMock = () => vi.mocked(globalThis.fetch);
 
   function jsonResponse<T>(body: T, init: ResponseInit = { status: 200 }) {
     return new Response(JSON.stringify(body), {
@@ -26,6 +21,11 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
     });
   }
 
+  beforeEach(() => {
+    fetchMock().mockReset();
+    vi.spyOn(comms, 'decryptValue').mockResolvedValue({ token: 'decrypted' });
+  });
+
   describe('getGiteaApiBaseUrl', () => {
     it('builds https api v1 base', () => {
       const url = getGiteaApiBaseUrl('gitea.example.com' as Hostname);
@@ -35,7 +35,7 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
 
   describe('listGiteaNotifications', () => {
     it('fetches a single page when fetchAllNotifications is false', async () => {
-      fetchSpy.mockResolvedValueOnce(jsonResponse([{ id: 1 }]));
+      fetchMock().mockResolvedValueOnce(jsonResponse([{ id: 1 }]));
 
       const result = await listGiteaNotifications(mockGiteaAccount, {
         fetchAllNotifications: false,
@@ -43,8 +43,8 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
       } as SettingsState);
 
       expect(result).toEqual([{ id: 1 }]);
-      expect(fetchSpy).toHaveBeenCalledTimes(1);
-      const calledUrl = fetchSpy.mock.calls[0][0] as string;
+      expect(fetchMock()).toHaveBeenCalledTimes(1);
+      const calledUrl = fetchMock().mock.calls[0][0] as string;
       expect(calledUrl).toContain('https://gitea.example.com/api/v1/');
       expect(calledUrl).toContain('status-types=unread');
       expect(calledUrl).toContain('page=1');
@@ -52,20 +52,20 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
     });
 
     it('includes read status when fetchReadNotifications is true', async () => {
-      fetchSpy.mockResolvedValueOnce(jsonResponse([]));
+      fetchMock().mockResolvedValueOnce(jsonResponse([]));
 
       await listGiteaNotifications(mockGiteaAccount, {
         fetchAllNotifications: false,
         fetchReadNotifications: true,
       } as SettingsState);
 
-      const calledUrl = fetchSpy.mock.calls[0][0] as string;
+      const calledUrl = fetchMock().mock.calls[0][0] as string;
       expect(calledUrl).toContain('status-types=unread');
       expect(calledUrl).toContain('status-types=read');
     });
 
     it('paginates until an empty page is returned', async () => {
-      fetchSpy
+      fetchMock()
         .mockResolvedValueOnce(jsonResponse(Array.from({ length: 100 }, (_, i) => ({ id: i }))))
         .mockResolvedValueOnce(jsonResponse([{ id: 100 }]))
         .mockResolvedValueOnce(jsonResponse([]));
@@ -76,11 +76,11 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
       } as SettingsState);
 
       expect(result).toHaveLength(101);
-      expect(fetchSpy).toHaveBeenCalledTimes(2);
+      expect(fetchMock()).toHaveBeenCalledTimes(2);
     });
 
     it('throws on a non-ok status without echoing the response body', async () => {
-      fetchSpy.mockResolvedValueOnce(
+      fetchMock().mockResolvedValue(
         new Response('Authorization: token leaked-pat', {
           status: 403,
           statusText: 'Forbidden',
@@ -106,22 +106,22 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
 
   describe('fetchGiteaAuthenticatedUser', () => {
     it('returns the user payload', async () => {
-      fetchSpy.mockResolvedValueOnce(jsonResponse({ id: 7, login: 'octocat' }));
+      fetchMock().mockResolvedValueOnce(jsonResponse({ id: 7, login: 'octocat' }));
 
       const result = await fetchGiteaAuthenticatedUser(mockGiteaAccount);
 
       expect(result).toEqual({ id: 7, login: 'octocat' });
-      expect(fetchSpy.mock.calls[0][0]).toContain('/api/v1/user');
+      expect(fetchMock().mock.calls[0][0]).toContain('/api/v1/user');
     });
   });
 
   describe('patchGiteaNotificationThread', () => {
     it('sends a PATCH with to-status query and resolves on 204', async () => {
-      fetchSpy.mockResolvedValueOnce(new Response(null, { status: 204 }));
+      fetchMock().mockResolvedValueOnce(new Response(null, { status: 204 }));
 
       await patchGiteaNotificationThread(mockGiteaAccount, '42', 'read');
 
-      const [url, init] = fetchSpy.mock.calls[0];
+      const [url, init] = fetchMock().mock.calls[0];
       expect(url).toContain('/notifications/threads/42?to-status=read');
       expect((init as RequestInit).method).toBe('PATCH');
     });
@@ -129,7 +129,7 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
 
   describe('giteaGetJson', () => {
     it('GETs the supplied URL with auth headers and parses JSON', async () => {
-      fetchSpy.mockResolvedValueOnce(jsonResponse({ html_url: 'x' }));
+      fetchMock().mockResolvedValueOnce(jsonResponse({ html_url: 'x' }));
 
       const result = await giteaGetJson<{ html_url: string }>(
         mockGiteaAccount,
@@ -137,12 +137,15 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
       );
 
       expect(result).toEqual({ html_url: 'x' });
-      const headers = (fetchSpy.mock.calls[0][1] as RequestInit).headers as Record<string, string>;
+      const headers = (fetchMock().mock.calls[0][1] as RequestInit).headers as Record<
+        string,
+        string
+      >;
       expect(headers.Authorization).toBe('token decrypted');
     });
 
     it('throws on a non-ok response without echoing the body', async () => {
-      fetchSpy.mockResolvedValueOnce(
+      fetchMock().mockResolvedValueOnce(
         new Response('echoed Authorization: token leaked-pat', {
           status: 500,
           statusText: 'Server Error',
@@ -158,21 +161,21 @@ describe('renderer/utils/forges/gitea/client.ts', () => {
       await expect(giteaGetJson(mockGiteaAccount, 'https://attacker.com/api/v1/x')).rejects.toThrow(
         /cross-origin Gitea URL/,
       );
-      expect(fetchSpy).not.toHaveBeenCalled();
+      expect(fetchMock()).not.toHaveBeenCalled();
     });
 
     it('refuses non-https URLs without sending a request', async () => {
       await expect(giteaGetJson(mockGiteaAccount, 'http://gitea.example.com/x')).rejects.toThrow(
         /cross-origin Gitea URL/,
       );
-      expect(fetchSpy).not.toHaveBeenCalled();
+      expect(fetchMock()).not.toHaveBeenCalled();
     });
 
     it('refuses malformed URLs without sending a request', async () => {
       await expect(giteaGetJson(mockGiteaAccount, 'not-a-url')).rejects.toThrow(
         /malformed Gitea URL/,
       );
-      expect(fetchSpy).not.toHaveBeenCalled();
+      expect(fetchMock()).not.toHaveBeenCalled();
     });
   });
 });
diff --git a/src/renderer/utils/forges/github/client.test.ts b/src/renderer/utils/forges/github/client.test.ts
index 2b74f0f7b..0c795e8a3 100644
--- a/src/renderer/utils/forges/github/client.test.ts
+++ b/src/renderer/utils/forges/github/client.test.ts
@@ -36,6 +36,15 @@ import type { OctokitClient } from './octokit';
 import * as octokitModule from './octokit';
 import * as apiRequests from './request';
 
+vi.mock('./request', async () => {
+  const actual = await vi.importActual<typeof import('./request')>('./request');
+  return {
+    ...actual,
+    performGraphQLRequest: vi.fn(),
+    performGraphQLRequestString: vi.fn(),
+  };
+});
+
 const mockThreadId = '1234';
 
 describe('renderer/utils/forges/github/client.ts', () => {
@@ -59,6 +68,9 @@ describe('renderer/utils/forges/github/client.ts', () => {
   const createOctokitClientUncachedSpy = vi.spyOn(octokitModule, 'createOctokitClientUncached');
 
   beforeEach(() => {
+    vi.mocked(apiRequests.performGraphQLRequest).mockReset();
+    vi.mocked(apiRequests.performGraphQLRequestString).mockReset();
+
     // Mock createOctokitClient to return our mock
     createOctokitClientSpy.mockResolvedValue(mockOctokit as unknown as OctokitClient);
     createOctokitClientUncachedSpy.mockResolvedValue(mockOctokit as unknown as OctokitClient);
@@ -270,7 +282,7 @@ describe('renderer/utils/forges/github/client.ts', () => {
   });
 
   it('fetchDiscussionByNumber calls performGraphQLRequest with correct args', async () => {
-    const performGraphQLRequestSpy = vi.spyOn(apiRequests, 'performGraphQLRequest');
+    const performGraphQLRequestSpy = vi.mocked(apiRequests.performGraphQLRequest);
 
     const mockNotification = mockPartialGitifyNotification({
       title: 'Some discussion',
@@ -298,7 +310,7 @@ describe('renderer/utils/forges/github/client.ts', () => {
   });
 
   it('fetchIssueByNumber calls performGraphQLRequest with correct args', async () => {
-    const performGraphQLRequestSpy = vi.spyOn(apiRequests, 'performGraphQLRequest');
+    const performGraphQLRequestSpy = vi.mocked(apiRequests.performGraphQLRequest);
 
     const mockNotification = mockPartialGitifyNotification({
       title: 'Some issue',
@@ -324,7 +336,7 @@ describe('renderer/utils/forges/github/client.ts', () => {
   });
 
   it('fetchPullByNumber calls performGraphQLRequest with correct args', async () => {
-    const performGraphQLRequestSpy = vi.spyOn(apiRequests, 'performGraphQLRequest');
+    const performGraphQLRequestSpy = vi.mocked(apiRequests.performGraphQLRequest);
 
     const mockNotification = mockPartialGitifyNotification({
       title: 'Some pull request',
@@ -355,7 +367,7 @@ describe('renderer/utils/forges/github/client.ts', () => {
 
   describe('fetchNotificationDetailsForList', () => {
     it('fetchNotificationDetailsForList returns empty map if no notifications', async () => {
-      const performGraphQLRequestStringSpy = vi.spyOn(apiRequests, 'performGraphQLRequestString');
+      const performGraphQLRequestStringSpy = vi.mocked(apiRequests.performGraphQLRequestString);
 
       const mockNotification = mockPartialGitifyNotification({
         title: 'Some commit',
@@ -371,7 +383,7 @@ describe('renderer/utils/forges/github/client.ts', () => {
     });
 
     it('fetchNotificationDetailsForList returns empty map if no supported notifications', async () => {
-      const performGraphQLRequestStringSpy = vi.spyOn(apiRequests, 'performGraphQLRequestString');
+      const performGraphQLRequestStringSpy = vi.mocked(apiRequests.performGraphQLRequestString);
 
       performGraphQLRequestStringSpy.mockResolvedValue({} as ExecutionResult<unknown>);
 
@@ -381,7 +393,7 @@ describe('renderer/utils/forges/github/client.ts', () => {
     });
 
     it('fetchNotificationDetailsForList returns empty map if no notifications', async () => {
-      const performGraphQLRequestStringSpy = vi.spyOn(apiRequests, 'performGraphQLRequestString');
+      const performGraphQLRequestStringSpy = vi.mocked(apiRequests.performGraphQLRequestString);
 
       performGraphQLRequestStringSpy.mockResolvedValue({
         data: {},
diff --git a/src/renderer/utils/forges/github/enrich.test.ts b/src/renderer/utils/forges/github/enrich.test.ts
index 8c21d08dc..7f468c0f9 100644
--- a/src/renderer/utils/forges/github/enrich.test.ts
+++ b/src/renderer/utils/forges/github/enrich.test.ts
@@ -7,6 +7,15 @@ import * as logger from '../../core/logger';
 import * as client from './client';
 import { enrichGitHubNotifications } from './enrich';
 
+vi.mock('./client', async () => {
+  const actual = await vi.importActual<typeof import('./client')>('./client');
+  return {
+    ...actual,
+    fetchNotificationDetailsForList: vi.fn(),
+    fetchIssueByNumber: vi.fn(),
+  };
+});
+
 describe('renderer/utils/forges/github/enrich.ts', () => {
   it('logs and continues when a per-notification handler throws', async () => {
     const rendererLogErrorSpy = vi.spyOn(logger, 'rendererLogError').mockImplementation(vi.fn());
@@ -14,7 +23,7 @@ describe('renderer/utils/forges/github/enrich.ts', () => {
 
     // No batched fragments — each handler will fall back to its single-fetch
     // path, which we make fail.
-    vi.spyOn(client, 'fetchNotificationDetailsForList').mockResolvedValue(new Map());
+    vi.mocked(client.fetchNotificationDetailsForList).mockResolvedValue(new Map());
 
     const mockError = new Error('Test error');
     const mockNotification = mockPartialGitifyNotification({
@@ -34,7 +43,7 @@ describe('renderer/utils/forges/github/enrich.ts', () => {
     };
     mockNotification.repository = mockRepository;
 
-    vi.spyOn(client, 'fetchIssueByNumber').mockRejectedValue(mockError);
+    vi.mocked(client.fetchIssueByNumber).mockRejectedValue(mockError);
 
     const [result] = await enrichGitHubNotifications([mockNotification], mockSettings);
 
diff --git a/src/renderer/utils/forges/github/enrich.ts b/src/renderer/utils/forges/github/enrich.ts
index 89b579b03..babfd57c6 100644
--- a/src/renderer/utils/forges/github/enrich.ts
+++ b/src/renderer/utils/forges/github/enrich.ts
@@ -38,12 +38,15 @@ async function fetchInBatches(
   notifications: RawGitifyNotification[],
 ): Promise<Map<RawGitifyNotification, FetchMergedDetailsTemplateQuery['repository']>> {
   const merged = new Map<RawGitifyNotification, FetchMergedDetailsTemplateQuery['repository']>();
+  const supportedNotifications = notifications.filter(
+    (notification) => createNotificationHandler(notification).supportsMergedQueryEnrichment,
+  );
 
   const batchSize = GITHUB_API_MERGE_BATCH_SIZE;
 
-  for (let start = 0; start < notifications.length; start += batchSize) {
+  for (let start = 0; start < supportedNotifications.length; start += batchSize) {
     const batchIndex = Math.floor(start / batchSize) + 1;
-    const slice = notifications.slice(start, start + batchSize);
+    const slice = supportedNotifications.slice(start, start + batchSize);
 
     try {
       const batchResults = await fetchNotificationDetailsForList(slice);
diff --git a/src/renderer/utils/forges/github/flows.test.ts b/src/renderer/utils/forges/github/flows.test.ts
index 8d18913f5..ce8c6c1fb 100644
--- a/src/renderer/utils/forges/github/flows.test.ts
+++ b/src/renderer/utils/forges/github/flows.test.ts
@@ -37,6 +37,7 @@ const exchangeWebFlowCodeMock = exchangeWebFlowCode as unknown as MockedFunction
 
 describe('renderer/utils/forges/github/flows.ts', () => {
   vi.spyOn(logger, 'rendererLogInfo').mockImplementation(vi.fn());
+  const rendererLogErrorSpy = vi.spyOn(logger, 'rendererLogError').mockImplementation(vi.fn());
   const openExternalLinkSpy = vi.spyOn(comms, 'openExternalLink').mockImplementation(vi.fn());
 
   beforeEach(() => {
@@ -136,6 +137,7 @@ describe('renderer/utils/forges/github/flows.ts', () => {
         await expect(
           async () => await flows.pollGitHubDeviceFlow(baseSession as DeviceFlowSession),
         ).rejects.toThrow('boom');
+        expect(rendererLogErrorSpy).toHaveBeenCalledTimes(1);
       });
     });
   });
diff --git a/src/renderer/utils/forges/github/handlers/discussion.test.ts b/src/renderer/utils/forges/github/handlers/discussion.test.ts
index 6e8f0fe41..a8b3b9a4a 100644
--- a/src/renderer/utils/forges/github/handlers/discussion.test.ts
+++ b/src/renderer/utils/forges/github/handlers/discussion.test.ts
@@ -20,6 +20,14 @@ import * as apiClient from '../client';
 import type { FetchDiscussionByNumberQuery } from '../graphql/generated/graphql';
 import { discussionHandler } from './discussion';
 
+vi.mock('../client', async () => {
+  const actual = await vi.importActual<typeof import('../client')>('../client');
+  return {
+    ...actual,
+    fetchDiscussionByNumber: vi.fn(),
+  };
+});
+
 describe('renderer/utils/notifications/handlers/discussion.ts', () => {
   describe('supportsMergedQueryEnrichment', () => {
     it('should support merge query', () => {
@@ -28,7 +36,7 @@ describe('renderer/utils/notifications/handlers/discussion.ts', () => {
   });
 
   describe('enrich', () => {
-    const fetchDiscussionByNumberSpy = vi.spyOn(apiClient, 'fetchDiscussionByNumber');
+    const fetchDiscussionByNumberSpy = vi.mocked(apiClient.fetchDiscussionByNumber);
 
     const mockNotification = mockPartialGitifyNotification({
       title: 'This is a mock discussion',
diff --git a/src/renderer/utils/forges/github/handlers/issue.test.ts b/src/renderer/utils/forges/github/handlers/issue.test.ts
index ae6c1dc97..fe1cecf19 100644
--- a/src/renderer/utils/forges/github/handlers/issue.test.ts
+++ b/src/renderer/utils/forges/github/handlers/issue.test.ts
@@ -14,6 +14,14 @@ import * as apiClient from '../client';
 import type { FetchIssueByNumberQuery } from '../graphql/generated/graphql';
 import { issueHandler } from './issue';
 
+vi.mock('../client', async () => {
+  const actual = await vi.importActual<typeof import('../client')>('../client');
+  return {
+    ...actual,
+    fetchIssueByNumber: vi.fn(),
+  };
+});
+
 describe('renderer/utils/notifications/handlers/issue.ts', () => {
   describe('supportsMergedQueryEnrichment', () => {
     it('should support merge query', () => {
@@ -22,7 +30,7 @@ describe('renderer/utils/notifications/handlers/issue.ts', () => {
   });
 
   describe('enrich', () => {
-    const fetchIssueByNumberSpy = vi.spyOn(apiClient, 'fetchIssueByNumber');
+    const fetchIssueByNumberSpy = vi.mocked(apiClient.fetchIssueByNumber);
 
     const mockNotification = mockPartialGitifyNotification({
       title: 'This is a mock issue',
diff --git a/src/renderer/utils/forges/github/handlers/pullRequest.test.ts b/src/renderer/utils/forges/github/handlers/pullRequest.test.ts
index 908507fb0..4b039f03f 100644
--- a/src/renderer/utils/forges/github/handlers/pullRequest.test.ts
+++ b/src/renderer/utils/forges/github/handlers/pullRequest.test.ts
@@ -22,6 +22,14 @@ import type {
 } from '../graphql/generated/graphql';
 import { getLatestReviewForReviewers, pullRequestHandler } from './pullRequest';
 
+vi.mock('../client', async () => {
+  const actual = await vi.importActual<typeof import('../client')>('../client');
+  return {
+    ...actual,
+    fetchPullByNumber: vi.fn(),
+  };
+});
+
 describe('renderer/utils/notifications/handlers/pullRequest.ts', () => {
   describe('mergeQueryConfig', () => {
     describe('supportsMergedQueryEnrichment', () => {
@@ -32,7 +40,7 @@ describe('renderer/utils/notifications/handlers/pullRequest.ts', () => {
   });
 
   describe('enrich', () => {
-    const fetchPullByNumberSpy = vi.spyOn(apiClient, 'fetchPullByNumber');
+    const fetchPullByNumberSpy = vi.mocked(apiClient.fetchPullByNumber);
 
     const mockNotification = mockPartialGitifyNotification({
       title: 'This is a mock pull request',
diff --git a/src/renderer/utils/notifications/notifications.test.ts b/src/renderer/utils/notifications/notifications.test.ts
index 01985ed9c..54d7953a9 100644
--- a/src/renderer/utils/notifications/notifications.test.ts
+++ b/src/renderer/utils/notifications/notifications.test.ts
@@ -26,7 +26,23 @@ import {
   stabilizeNotificationsOrder,
 } from './notifications';
 
+vi.mock('../forges/github/client', async () => {
+  const actual =
+    await vi.importActual<typeof import('../forges/github/client')>('../forges/github/client');
+  return {
+    ...actual,
+    fetchNotificationDetailsForList: vi.fn(),
+    fetchIssueByNumber: vi.fn(),
+  };
+});
+
 describe('renderer/utils/notifications/notifications.ts', () => {
+  beforeEach(() => {
+    vi.mocked(apiClient.fetchNotificationDetailsForList).mockReset();
+    vi.mocked(apiClient.fetchNotificationDetailsForList).mockResolvedValue(new Map());
+    vi.mocked(apiClient.fetchIssueByNumber).mockReset();
+  });
+
   it('getNotificationCount', () => {
     const result = getNotificationCount(mockSingleAccountNotifications);
 
@@ -122,6 +138,7 @@ describe('renderer/utils/notifications/notifications.ts', () => {
 
       expect(result).toHaveLength(1);
       expect(result[0].subject.title).toBe('CI workflow run');
+      expect(apiClient.fetchNotificationDetailsForList).not.toHaveBeenCalled();
     });
 
     it('should handle empty notifications array', async () => {
@@ -133,12 +150,15 @@ describe('renderer/utils/notifications/notifications.ts', () => {
       const result = await enrichNotifications([], settings);
 
       expect(result).toEqual([]);
+      expect(apiClient.fetchNotificationDetailsForList).not.toHaveBeenCalled();
     });
 
     it('should batch notifications by GITHUB_API_MERGE_BATCH_SIZE', async () => {
-      const fetchNotificationDetailsForListSpy = vi
-        .spyOn(apiClient, 'fetchNotificationDetailsForList')
-        .mockResolvedValue(new Map());
+      const fetchNotificationDetailsForListSpy = vi.mocked(
+        apiClient.fetchNotificationDetailsForList,
+      );
+      vi.mocked(apiClient.fetchIssueByNumber).mockResolvedValue({ repository: {} } as never);
+      fetchNotificationDetailsForListSpy.mockResolvedValue(new Map());
 
       const notificationCount = GITHUB_API_MERGE_BATCH_SIZE * 2.5;
       const notifications = Array.from({ length: notificationCount }, (_, i) =>
@@ -170,9 +190,11 @@ describe('renderer/utils/notifications/notifications.ts', () => {
     });
 
     it('should handle single batch of notifications', async () => {
-      const fetchNotificationDetailsForListSpy = vi
-        .spyOn(apiClient, 'fetchNotificationDetailsForList')
-        .mockResolvedValue(new Map());
+      const fetchNotificationDetailsForListSpy = vi.mocked(
+        apiClient.fetchNotificationDetailsForList,
+      );
+      vi.mocked(apiClient.fetchIssueByNumber).mockResolvedValue({ repository: {} } as never);
+      fetchNotificationDetailsForListSpy.mockResolvedValue(new Map());
 
       const notifications = Array.from({ length: 50 }, (_, i) =>
         mockPartialGitifyNotification({
diff --git a/vitest.config.ts b/vitest.config.ts
index 9cfa4954b..3fcebed24 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -8,6 +8,8 @@ export default defineConfig({
     pool: 'vmThreads',
     isolate: false,
     clearMocks: true,
+    unstubEnvs: true,
+    unstubGlobals: true,
     // Pre-bundle @primer/react rather than re-transforming the raw package on every thread load.
     // See https://vitest.dev/guide/profiling-test-performance.html#use-the-dependency-optimizer
     deps: {