diff --git a/packages/playwright-core/src/server/bidi/bidiBrowser.ts b/packages/playwright-core/src/server/bidi/bidiBrowser.ts
index 5c1cb400d1..1f376c820d 100644
--- a/packages/playwright-core/src/server/bidi/bidiBrowser.ts
+++ b/packages/playwright-core/src/server/bidi/bidiBrowser.ts
@@ -20,7 +20,7 @@ import { BrowserContext, assertBrowserContextIsNotOwned } from '../browserContex
 import * as network from '../network';
 import { BidiConnection } from './bidiConnection';
 import { bidiBytesValueToString } from './bidiNetworkManager';
-import { BidiPage } from './bidiPage';
+import { addMainBinding, BidiPage, kPlaywrightBindingChannel } from './bidiPage';
 import * as bidi from './third_party/bidiProtocol';
 
 import type { RegisteredListener } from '../utils/eventsHelper';
@@ -203,6 +203,7 @@ export class BidiBrowser extends Browser {
 
 export class BidiBrowserContext extends BrowserContext {
   declare readonly _browser: BidiBrowser;
+  private _initScriptIds: bidi.Script.PreloadScript[] = [];
 
   constructor(browser: BidiBrowser, browserContextId: string | undefined, options: types.BrowserContextOptions) {
     super(browser, options, browserContextId);
@@ -213,6 +214,45 @@ export class BidiBrowserContext extends BrowserContext {
     return [...this._browser._bidiPages.values()].filter(bidiPage => bidiPage._browserContext === this);
   }
 
+  override async _initialize() {
+    const promises: Promise<any>[] = [
+      super._initialize(),
+      this._installMainBinding(),
+    ];
+    // FIXME: Persistent context doesn't have an id, so we can't set the command for it.
+    if (this._options.viewport && this._browserContextId) {
+      promises.push(this._browser._browserSession.send('browsingContext.setViewport', {
+        viewport: {
+          width: this._options.viewport.width,
+          height: this._options.viewport.height
+        },
+        devicePixelRatio: this._options.deviceScaleFactor || 1,
+        userContexts: [this._browserContextId],
+      }));
+    }
+    await Promise.all(promises);
+  }
+
+  // TODO: consider calling this only when bindings are added.
+  private async _installMainBinding() {
+    // TODO: Cannot install main binding for persistent context as it doesn't have an id.
+    if (!this._browserContextId)
+      return;
+    const functionDeclaration = addMainBinding.toString();
+    const args: bidi.Script.ChannelValue[] = [{
+      type: 'channel',
+      value: {
+        channel: kPlaywrightBindingChannel,
+        ownership: bidi.Script.ResultOwnership.Root,
+      }
+    }];
+    await this._browser._browserSession.send('script.addPreloadScript', {
+      functionDeclaration,
+      arguments: args,
+      userContexts: [this._browserContextId],
+    });
+  }
+
   override possiblyUninitializedPages(): Page[] {
     return this._bidiPages().map(bidiPage => bidiPage._page);
   }
@@ -293,10 +333,22 @@ export class BidiBrowserContext extends BrowserContext {
   }
 
   async doAddInitScript(initScript: InitScript) {
-    await Promise.all(this.pages().map(page => (page._delegate as BidiPage).addInitScript(initScript)));
+    // TODO: support persistent context.
+    if (!this._browserContextId)
+      return;
+    const { script } = await this._browser._browserSession.send('script.addPreloadScript', {
+      // TODO: remove function call from the source.
+      functionDeclaration: `() => { return ${initScript.source} }`,
+      userContexts: [this._browserContextId],
+    });
+    if (!initScript.internal)
+      this._initScriptIds.push(script);
   }
 
   async doRemoveNonInternalInitScripts() {
+    const promise = Promise.all(this._initScriptIds.map(script => this._browser._browserSession.send('script.removePreloadScript', { script })));
+    this._initScriptIds = [];
+    await promise;
   }
 
   async doUpdateRequestInterception(): Promise<void> {
diff --git a/packages/playwright-core/src/server/bidi/bidiPage.ts b/packages/playwright-core/src/server/bidi/bidiPage.ts
index 13cb21e36f..76267ab89c 100644
--- a/packages/playwright-core/src/server/bidi/bidiPage.ts
+++ b/packages/playwright-core/src/server/bidi/bidiPage.ts
@@ -37,7 +37,7 @@ import type { BidiSession } from './bidiConnection';
 import type * as channels from '@protocol/channels';
 
 const UTILITY_WORLD_NAME = '__playwright_utility_world__';
-const kPlaywrightBindingChannel = 'playwrightChannel';
+export const kPlaywrightBindingChannel = 'playwrightChannel';
 
 export class BidiPage implements PageDelegate {
   readonly rawMouse: RawMouseImpl;
@@ -51,7 +51,7 @@ export class BidiPage implements PageDelegate {
   readonly _browserContext: BidiBrowserContext;
   readonly _networkManager: BidiNetworkManager;
   private readonly _pdf: BidiPDF;
-  private _initScriptIds: string[] = [];
+  private _initScriptIds: bidi.Script.PreloadScript[] = [];
 
   constructor(browserContext: BidiBrowserContext, bidiSession: BidiSession, opener: BidiPage | null) {
     this._session = bidiSession;
@@ -92,7 +92,6 @@ export class BidiPage implements PageDelegate {
     await Promise.all([
       this.updateHttpCredentials(),
       this.updateRequestInterception(),
-      this._updateViewport(),
       this._installMainBinding(),
       this._addAllInitScripts(),
     ]);
@@ -258,10 +257,6 @@ export class BidiPage implements PageDelegate {
   async updateEmulateMedia(): Promise<void> {
   }
 
-  async updateEmulatedViewportSize(): Promise<void> {
-    await this._updateViewport();
-  }
-
   async updateUserAgent(): Promise<void> {
   }
 
@@ -271,7 +266,7 @@ export class BidiPage implements PageDelegate {
     });
   }
 
-  private async _updateViewport(): Promise<void> {
+  async updateEmulatedViewportSize(): Promise<void> {
     const options = this._browserContext._options;
     const deviceSize = this._page.emulatedSize();
     if (deviceSize === null)
@@ -328,7 +323,11 @@ export class BidiPage implements PageDelegate {
   }
 
   // TODO: consider calling this only when bindings are added.
+  // TODO: delete this method once we can add preload script for persistent context.
   private async _installMainBinding() {
+    // For non-persistent context, the main binding is installed during context creation.
+    if (this._browserContext._browserContextId)
+      return;
     const functionDeclaration = addMainBinding.toString();
     const args: bidi.Script.ChannelValue[] = [{
       type: 'channel',
@@ -573,7 +572,7 @@ export class BidiPage implements PageDelegate {
   }
 }
 
-function addMainBinding(callback: (arg: any) => void) {
+export function addMainBinding(callback: (arg: any) => void) {
   (globalThis as any)['__playwright__binding__'] = callback;
 }