diff --git a/packages/playwright-core/src/server/browserType.ts b/packages/playwright-core/src/server/browserType.ts
index 24a057ebf9..617824a489 100644
--- a/packages/playwright-core/src/server/browserType.ts
+++ b/packages/playwright-core/src/server/browserType.ts
@@ -133,7 +133,7 @@ export abstract class BrowserType extends SdkObject {
     if (persistent)
       validateBrowserContextOptions(persistent, browserOptions);
     copyTestHooks(options, browserOptions);
-    const browser = await this._connectToTransport(transport, browserOptions);
+    const browser = await this.connectToTransport(transport, browserOptions);
     (browser as any)._userDataDirForTest = userDataDir;
     // We assume no control when using custom arguments, and do not prepare the default context in that case.
     if (persistent && !options.ignoreAllDefaultArgs)
@@ -173,9 +173,9 @@ export abstract class BrowserType extends SdkObject {
     if (ignoreAllDefaultArgs)
       browserArguments.push(...args);
     else if (ignoreDefaultArgs)
-      browserArguments.push(...this._defaultArgs(options, isPersistent, userDataDir).filter(arg => ignoreDefaultArgs.indexOf(arg) === -1));
+      browserArguments.push(...this.defaultArgs(options, isPersistent, userDataDir).filter(arg => ignoreDefaultArgs.indexOf(arg) === -1));
     else
-      browserArguments.push(...this._defaultArgs(options, isPersistent, userDataDir));
+      browserArguments.push(...this.defaultArgs(options, isPersistent, userDataDir));
 
     let executable: string;
     if (executablePath) {
@@ -199,7 +199,7 @@ export abstract class BrowserType extends SdkObject {
     const { launchedProcess, gracefullyClose, kill } = await launchProcess({
       command: executable,
       args: browserArguments,
-      env: this._amendEnvironment(env, userDataDir, executable, browserArguments),
+      env: this.amendEnvironment(env, userDataDir, executable, browserArguments),
       handleSIGINT,
       handleSIGTERM,
       handleSIGHUP,
@@ -222,7 +222,7 @@ export abstract class BrowserType extends SdkObject {
         // We try to gracefully close to prevent crash reporting and core dumps.
         // Note that it's fine to reuse the pipe transport, since
         // our connection ignores kBrowserCloseMessageId.
-        this._attemptToGracefullyCloseBrowser(transport!);
+        this.attemptToGracefullyCloseBrowser(transport!);
       },
       onExit: (exitCode, signal) => {
         // Unblock launch when browser prematurely exits.
@@ -305,14 +305,14 @@ export abstract class BrowserType extends SdkObject {
   _rewriteStartupLog(error: Error): Error {
     if (!isProtocolError(error))
       return error;
-    return this._doRewriteStartupLog(error);
+    return this.doRewriteStartupLog(error);
   }
 
-  abstract _defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[];
-  abstract _connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<Browser>;
-  abstract _amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env;
-  abstract _doRewriteStartupLog(error: ProtocolError): ProtocolError;
-  abstract _attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void;
+  abstract defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[];
+  abstract connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<Browser>;
+  abstract amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env;
+  abstract doRewriteStartupLog(error: ProtocolError): ProtocolError;
+  abstract attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void;
 }
 
 function copyTestHooks(from: object, to: object) {
diff --git a/packages/playwright-core/src/server/chromium/chromium.ts b/packages/playwright-core/src/server/chromium/chromium.ts
index e745cca214..f86e1f71d4 100644
--- a/packages/playwright-core/src/server/chromium/chromium.ts
+++ b/packages/playwright-core/src/server/chromium/chromium.ts
@@ -131,7 +131,7 @@ export class Chromium extends BrowserType {
     return directory ? new CRDevTools(path.join(directory, 'devtools-preferences.json')) : undefined;
   }
 
-  async _connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<CRBrowser> {
+  override async connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<CRBrowser> {
     let devtools = this._devtools;
     if ((options as any).__testHookForDevTools) {
       devtools = this._createDevTools();
@@ -140,7 +140,7 @@ export class Chromium extends BrowserType {
     return CRBrowser.connect(this.attribution.playwright, transport, options, devtools);
   }
 
-  _doRewriteStartupLog(error: ProtocolError): ProtocolError {
+  override doRewriteStartupLog(error: ProtocolError): ProtocolError {
     if (!error.logs)
       return error;
     if (error.logs.includes('Missing X server'))
@@ -161,11 +161,11 @@ export class Chromium extends BrowserType {
     return error;
   }
 
-  _amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env {
+  override amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env {
     return env;
   }
 
-  _attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void {
+  override attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void {
     const message: ProtocolRequest = { method: 'Browser.close', id: kBrowserCloseMessageId, params: {} };
     transport.send(message);
   }
@@ -277,7 +277,7 @@ export class Chromium extends BrowserType {
     }
   }
 
-  _defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[] {
+  override defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[] {
     const chromeArguments = this._innerDefaultArgs(options);
     chromeArguments.push(`--user-data-dir=${userDataDir}`);
     if (options.useWebSocket)
diff --git a/packages/playwright-core/src/server/firefox/firefox.ts b/packages/playwright-core/src/server/firefox/firefox.ts
index 96d1edae4c..885291cf0b 100644
--- a/packages/playwright-core/src/server/firefox/firefox.ts
+++ b/packages/playwright-core/src/server/firefox/firefox.ts
@@ -33,11 +33,11 @@ export class Firefox extends BrowserType {
     super(parent, 'firefox');
   }
 
-  _connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<FFBrowser> {
+  override connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<FFBrowser> {
     return FFBrowser.connect(this.attribution.playwright, transport, options);
   }
 
-  _doRewriteStartupLog(error: ProtocolError): ProtocolError {
+  override doRewriteStartupLog(error: ProtocolError): ProtocolError {
     if (!error.logs)
       return error;
     // https://github.com/microsoft/playwright/issues/6500
@@ -48,7 +48,7 @@ export class Firefox extends BrowserType {
     return error;
   }
 
-  _amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env {
+  override amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env {
     if (!path.isAbsolute(os.homedir()))
       throw new Error(`Cannot launch Firefox with relative home directory. Did you set ${os.platform() === 'win32' ? 'USERPROFILE' : 'HOME'} to a relative path?`);
     if (os.platform() === 'linux') {
@@ -60,12 +60,12 @@ export class Firefox extends BrowserType {
     return env;
   }
 
-  _attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void {
+  override attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void {
     const message = { method: 'Browser.close', params: {}, id: kBrowserCloseMessageId };
     transport.send(message);
   }
 
-  _defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[] {
+  override defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[] {
     const { args = [], headless } = options;
     const userDataDirArg = args.find(arg => arg.startsWith('-profile') || arg.startsWith('--profile'));
     if (userDataDirArg)
diff --git a/packages/playwright-core/src/server/playwright.ts b/packages/playwright-core/src/server/playwright.ts
index c4ffd518ce..3d524ad959 100644
--- a/packages/playwright-core/src/server/playwright.ts
+++ b/packages/playwright-core/src/server/playwright.ts
@@ -28,6 +28,7 @@ import { debugLogger } from '../utils/debugLogger';
 import type { Page } from './page';
 import { DebugController } from './debugController';
 import type { Language } from '../utils/isomorphic/locatorGenerators';
+import type { BrowserType } from './browserType';
 
 type PlaywrightOptions = {
   socksProxyPort?: number;
@@ -38,11 +39,11 @@ type PlaywrightOptions = {
 
 export class Playwright extends SdkObject {
   readonly selectors: Selectors;
-  readonly chromium: Chromium;
+  readonly chromium: BrowserType;
   readonly android: Android;
   readonly electron: Electron;
-  readonly firefox: Firefox;
-  readonly webkit: WebKit;
+  readonly firefox: BrowserType;
+  readonly webkit: BrowserType;
   readonly options: PlaywrightOptions;
   readonly debugController: DebugController;
   private _allPages = new Set<Page>();
diff --git a/packages/playwright-core/src/server/webkit/webkit.ts b/packages/playwright-core/src/server/webkit/webkit.ts
index 33f4a68c20..b25b62a421 100644
--- a/packages/playwright-core/src/server/webkit/webkit.ts
+++ b/packages/playwright-core/src/server/webkit/webkit.ts
@@ -32,15 +32,15 @@ export class WebKit extends BrowserType {
     super(parent, 'webkit');
   }
 
-  _connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<WKBrowser> {
+  override connectToTransport(transport: ConnectionTransport, options: BrowserOptions): Promise<WKBrowser> {
     return WKBrowser.connect(this.attribution.playwright, transport, options);
   }
 
-  _amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env {
+  override amendEnvironment(env: Env, userDataDir: string, executable: string, browserArguments: string[]): Env {
     return { ...env, CURL_COOKIE_JAR_PATH: path.join(userDataDir, 'cookiejar.db') };
   }
 
-  _doRewriteStartupLog(error: ProtocolError): ProtocolError {
+  override doRewriteStartupLog(error: ProtocolError): ProtocolError {
     if (!error.logs)
       return error;
     if (error.logs.includes('cannot open display'))
@@ -48,11 +48,11 @@ export class WebKit extends BrowserType {
     return error;
   }
 
-  _attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void {
+  override attemptToGracefullyCloseBrowser(transport: ConnectionTransport): void {
     transport.send({ method: 'Playwright.close', params: {}, id: kBrowserCloseMessageId });
   }
 
-  _defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[] {
+  override defaultArgs(options: types.LaunchOptions, isPersistent: boolean, userDataDir: string): string[] {
     const { args = [], proxy, headless } = options;
     const userDataDirArg = args.find(arg => arg.startsWith('--user-data-dir'));
     if (userDataDirArg)
diff --git a/tests/library/defaultbrowsercontext-2.spec.ts b/tests/library/defaultbrowsercontext-2.spec.ts
index 3552f94e97..a54f4ee15a 100644
--- a/tests/library/defaultbrowsercontext-2.spec.ts
+++ b/tests/library/defaultbrowsercontext-2.spec.ts
@@ -144,7 +144,7 @@ it('should have passed URL when launching with ignoreDefaultArgs: true', async (
   it.skip(mode !== 'default');
 
   const userDataDir = await createUserDataDir();
-  const args = toImpl(browserType)._defaultArgs((browserType as any)._defaultLaunchOptions, 'persistent', userDataDir, 0).filter(a => a !== 'about:blank');
+  const args = toImpl(browserType).defaultArgs((browserType as any)._defaultLaunchOptions, 'persistent', userDataDir, 0).filter(a => a !== 'about:blank');
   const options = {
     args: browserName === 'firefox' ? [...args, '-new-tab', server.EMPTY_PAGE] : [...args, server.EMPTY_PAGE],
     ignoreDefaultArgs: true,