For applications requiring enhanced functional capabilities, providing your own Chrome extension is a great option. With Browserbase, using extensions is easy.

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Sample Extension

Here’s a simple example extension that modifies page titles. It consists of two files: 
{
    "manifest_version": 3,
    "version": "1.0",
    "name": "My Test Extension",
    "description": "Test of a simple browser extension",
    "content_scripts": [
        {
            "matches": [
                "https://www.sfmoma.org/*"
            ],
            "js": [
                "content-script.js"
            ]
        }
    ]
}
You can download this sample extension here. The extension must be in a .zip file format with a manifest.json at the root. The file must be less than or equal to 100 MB.

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Upload Your Extension

Once you have your extension files zipped up, you can upload it using our SDK: 
from browserbase import Browserbase

bb = Browserbase(api_key="your-api-key")

# Upload the extension
with open("extension.zip", "rb") as f:
    extension = bb.extensions.create(f)

extension_id = extension.id
print(f"Extension uploaded with ID: {extension_id}")

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Create a Session with Your Extension

To use your extension, create a new session with the extension enabled: 
from browserbase import Browserbase

bb = Browserbase(api_key="your-api-key")

# Create a session with the extension
session = bb.sessions.create(
    project_id="your-project-id",
    extension_id="your-extension-id"
)

print(f"Session created with ID: {session.id}")
Starting a new session with an extension can increase the session creation time. The browser must be restarted to load the extension, which itself has nonzero load time.

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Verify the Extension

To verify your extension is working:
  1. Connect to your session using Playwright or Selenium
  2. Navigate to a page where your extension should be active
  3. Check for the expected modifications or behaviors
For the sample extension above, navigate to https://www.sfmoma.org and verify that the page title has been modified with the additional text.