Key features of Avast Secure Browser typically include:

1. Security and Privacy Features: The browser often comes with built-in features to enhance online security and privacy, such as anti-phishing protection, anti-tracking tools, and a secure HTTPS connection.
2. Ad Blocker: Avast Secure Browser may include an integrated ad blocker to help users browse the internet without intrusive advertisements.
3. Bank Mode: Some versions of the browser have a “Bank Mode” or “Secure Mode” that provides an extra layer of security when conducting online banking transactions or entering sensitive information.
4. Password Manager: There may be a password manager integrated into the browser to help users securely store and manage their passwords.
5. Extension Guard: The browser might have features to protect against malicious browser extensions and add-ons.
6. Performance Features: Avast Secure Browser may include optimizations for speed and performance to provide a smooth browsing experience.

It’s important to note that software and its features can change over time, and new versions may have been released since my last update. Therefore, for the most accurate and up-to-date information, I recommend checking the official Avast website or other reliable sources for the latest details on Avast Secure Browser as of the current date in 2023.