Mozilla Firefox as a Linux alternative to Opera

Updated October 18, 2026

Our verdict

Mozilla Firefox is a strong, stable replacement for Opera if you can live without the built-in VPN. It handles fast page loading, offers a highly customizable interface, and supports the same extension ecosystem. However, it lacks Opera's integrated ad blocker and privacy tools out of the box. You will need to install add-ons like uBlock Origin to match Opera's default privacy stance. If the built-in VPN is your primary reason for using Opera, Firefox is not a direct drop-in replacement. For users who prioritize open-source transparency and don't mind configuring their own privacy stack, Firefox is an excellent choice.

Feature parity85%

License: MPL-2.0
Price: Free
Latest version: —
Rating: —

Install Mozilla Firefox

What works the same

Supports a vast ecosystem of extensions and add-ons
Allows deep UI customization, including themes and layout changes
Receives regular security updates and patches
Provides fast page loading performance
Supports multiple profiles for separate browsing sessions

What is different

Lacks a built-in VPN; requires third-party services or add-ons
No built-in ad blocker; must install extensions like uBlock Origin
Open-source model (MPL-2.0) versus Opera's proprietary codebase
Does not include Opera's built-in crypto wallet or news aggregator
Different default search engine and privacy tracking protection implementation

Opening your Opera files

Firefox can import bookmarks, passwords, and history directly from Opera during initial setup if Opera is installed on the same machine. If migrating from a Windows machine to Linux, you must export bookmarks from Opera to an HTML file and import that file into Firefox. Opera-specific profile data or internal settings do not transfer. Passwords can be exported from Opera to a CSV file and imported into Firefox, though you should handle this file securely as it contains sensitive credentials.

Switching from Opera to Mozilla Firefox, step by step

Export bookmarks from Opera to an HTML file
Export passwords from Opera to a CSV file
Install Mozilla Firefox on your Linux system
Import the HTML bookmarks file into Firefox
Import the CSV password file into Firefox
Install essential extensions like uBlock Origin to replace built-in ad blocking

Key features of Mozilla Firefox

Extensive add‑on ecosystem
Built‑in tracking protection
Customizable UI via CSS
Regular security updates
Multi‑profile support
Integrated Pocket reading list

Frequently asked questions

Does Firefox have a built-in VPN like Opera?

No, Firefox does not include a built-in VPN. You will need to use a third-party VPN service or install a VPN add-on if available, but it is not integrated into the browser core.

Can I customize Firefox to look like Opera?

Yes, Firefox supports extensive customization via CSS and themes. You can change colors, fonts, and layout to closely resemble Opera's interface, though some specific Opera widgets may not have direct equivalents.

Is Firefox's ad blocking as good as Opera's built-in feature?

Firefox has built-in tracking protection, but it is less aggressive than Opera's ad blocker. To match or exceed Opera's performance, you should install the uBlock Origin extension, which is widely considered the standard for ad blocking.