Fix moz-extension:// navigation hang by bypassing geckodriver

src/firefox/index.ts

@@ -74,7 +74,8 @@ export class FirefoxClient {
     this.pages = new PageManagement(
       driver,
       () => this.core.getCurrentContextId(),
-      (id: string) => this.core.setCurrentContextId(id)
+      (id: string) => this.core.setCurrentContextId(id),
+      (method: string, params: Record<string, any>) => this.core.sendBiDiCommand(method, params)
     );
 
     // Subscribe to console and network events for ALL contexts (not just current).

src/firefox/pages.ts

@@ -3,20 +3,53 @@
  */
 
 import { WebDriver } from 'selenium-webdriver';
-import { log } from '../utils/logger.js';
+import { log, logDebug } from '../utils/logger.js';
+
+const COMMON_URL_SCHEMES = ['http:', 'https:', 'data:', 'blob:', 'file:'];
+
+/**
+ * Check if a URL uses a common scheme that supports load events.
+ * Non-common schemes = moz-extension:, about:, ...
+ */
+export function isCommonScheme(url: string): boolean {
+  try {
+    return COMMON_URL_SCHEMES.includes(new URL(url).protocol);
+  } catch {
+    return false;
+  }
+}
+
+export type BiDiCommandFn = (method: string, params: Record<string, any>) => Promise<any>;
 
 export class PageManagement {
   constructor(
     private driver: WebDriver,
     private getCurrentContextId: () => string | null,
-    private setCurrentContextId: (id: string) => void
+    private setCurrentContextId: (id: string) => void,
+    private sendBiDiCommand: BiDiCommandFn
   ) {}
 
   /**
-   * Navigate to URL
+   * Navigate to URL using BiDi
    */
   async navigate(url: string): Promise<void> {
-    await this.driver.get(url);
+    const contextId = this.getCurrentContextId();
+    if (!contextId) {
+      throw new Error(`Cannot navigate: no browsing context ID`);
+    }
+
+    // Default wait time is "interactive" (DOMContentLoaded).
+    // All uncommon schemes use wait time "none"
+    const wait = isCommonScheme(url) ? 'interactive' : 'none';
+
+    // Navigate using direct BiDi
+    await this.sendBiDiCommand('browsingContext.navigate', {
+      context: contextId,
+      url,
+      wait,
+    });
+
+    logDebug(`BiDi navigate (wait:${wait}) to: ${url}`);
     log(`Navigated to: ${url}`);
   }
 
@@ -159,7 +192,7 @@ export class PageManagement {
     const newIdx = handles.length - 1;
     this.setCurrentContextId(handles[newIdx]!);
     this.cachedSelectedIdx = newIdx;
-    await this.driver.get(url);
+    await this.navigate(url);
     return newIdx;
   }
 

tests/firefox/pages.test.ts

@@ -0,0 +1,174 @@
+/**
+ * Unit tests for PageManagement and isCommonScheme
+ *
+ * Navigation uses BiDi browsingContext.navigate for all URLs.
+ * Common schemes (http/https/data/blob/file) use wait:"interactive".
+ * Uncommon schemes (moz-extension:, about:, etc.) use wait:"none"
+ */
+
+import { describe, it, expect, vi } from 'vitest';
+import { isCommonScheme, PageManagement } from '@/firefox/pages.js';
+
+const HTTPS_URL = 'https://example.com/test.html';
+const HTTP_URL = 'http://example.com/test.html';
+const FILE_URL = 'file:///some/path/test.html';
+const MOZ_EXT_URL = 'moz-extension://a1b2c3d4-e5f6-7890-abcd-ef1234567890/popup.html';
+const BLOB_URL = 'blob:https://example.org/40a5fb5a-d56d-4a33-b4e2-0acf6a8e5f64';
+const DATA_URL = 'data:text/plain;base64,SGVsbG8sIFdvcmxkIQ==';
+
+describe('isCommonScheme', () => {
+  it('returns true for common URL schemes', () => {
+    expect(isCommonScheme(HTTPS_URL)).toBe(true);
+    expect(isCommonScheme(HTTP_URL)).toBe(true);
+    expect(isCommonScheme(FILE_URL)).toBe(true);
+    expect(isCommonScheme(DATA_URL)).toBe(true);
+    expect(isCommonScheme(BLOB_URL)).toBe(true);
+  });
+
+  it('returns false for moz-extension:// URLs', () => {
+    expect(isCommonScheme(MOZ_EXT_URL)).toBe(false);
+  });
+
+  it('returns false for about: URLs', () => {
+    expect(isCommonScheme('about:blank')).toBe(false);
+  });
+
+  it('returns false for malformed URLs', () => {
+    expect(isCommonScheme('not-a-url')).toBe(false);
+  });
+});
+
+// -- PageManagement -----------------------------------------------------------
+
+describe('PageManagement', () => {
+  function createMocks() {
+    // Any driver method call should fail — navigate must use BiDi, not driver
+    const driver = new Proxy(
+      {},
+      {
+        get: () => {
+          throw new Error('Unexpected driver call — navigation must use BiDi');
+        },
+      }
+    );
+    const getCurrentContextId = vi.fn().mockReturnValue('ctx-1');
+    const setCurrentContextId = vi.fn();
+    const sendBiDiCommand = vi.fn().mockResolvedValue({});
+
+    const pages = new PageManagement(
+      driver,
+      getCurrentContextId,
+      setCurrentContextId,
+      sendBiDiCommand
+    );
+    return { pages, sendBiDiCommand };
+  }
+
+  describe('navigate', () => {
+    it('uses BiDi with wait:interactive for common URL schemes', async () => {
+      const { pages, sendBiDiCommand } = createMocks();
+
+      await pages.navigate(HTTPS_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: HTTPS_URL,
+        wait: 'interactive',
+      });
+
+      await pages.navigate(HTTP_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: HTTP_URL,
+        wait: 'interactive',
+      });
+
+      await pages.navigate(DATA_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: DATA_URL,
+        wait: 'interactive',
+      });
+
+      await pages.navigate(FILE_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: FILE_URL,
+        wait: 'interactive',
+      });
+
+      await pages.navigate(BLOB_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: BLOB_URL,
+        wait: 'interactive',
+      });
+    });
+
+    it('uses BiDi with wait:none for uncommon URL schemes', async () => {
+      const { pages, sendBiDiCommand } = createMocks();
+
+      await pages.navigate(MOZ_EXT_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: MOZ_EXT_URL,
+        wait: 'none',
+      });
+
+      await pages.navigate('about:blank');
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: 'about:blank',
+        wait: 'none',
+      });
+
+      await pages.navigate('not-a-url');
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'ctx-1',
+        url: 'not-a-url',
+        wait: 'none',
+      });
+    });
+  });
+
+  describe('createNewPage', () => {
+    it('uses BiDi navigate', async () => {
+      // createNewPage needs real driver methods for switchTo/handles
+      const switchToMock = vi
+        .fn()
+        .mockReturnValue({ newWindow: vi.fn().mockResolvedValue(undefined) });
+      const getAllWindowHandlesMock = vi.fn().mockResolvedValue(['handle-1', 'handle-2']);
+
+      const driver = {
+        switchTo: switchToMock,
+        getAllWindowHandles: getAllWindowHandlesMock,
+      } as any;
+
+      const getCurrentContextId = vi.fn().mockReturnValue('handle-2');
+      const setCurrentContextId = vi.fn();
+      const sendBiDiCommand = vi.fn().mockResolvedValue({});
+
+      const pages = new PageManagement(
+        driver,
+        getCurrentContextId,
+        setCurrentContextId,
+        sendBiDiCommand
+      );
+
+      // wait: interactive
+      await pages.createNewPage(HTTPS_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'handle-2',
+        url: HTTPS_URL,
+        wait: 'interactive',
+      });
+
+      // wait: none
+      await pages.createNewPage(MOZ_EXT_URL);
+      expect(sendBiDiCommand).toHaveBeenCalledWith('browsingContext.navigate', {
+        context: 'handle-2',
+        url: MOZ_EXT_URL,
+        wait: 'none',
+      });
+    });
+  });
+});

tests/fixtures/test-extension/manifest.json

@@ -0,0 +1,9 @@
+{
+  "manifest_version": 2,
+  "name": "MCP Test Extension",
+  "version": "1.0",
+  "description": "Minimal extension for testing moz-extension:// navigation",
+  "browser_action": {
+    "default_popup": "popup.html"
+  }
+}

tests/fixtures/test-extension/popup.html

@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>MCP Test Extension</title>
+</head>
+<body>
+  <h1>MCP Test Extension</h1>
+  <p id="status">extension-loaded</p>
+</body>
+</html>