What’s New in Mozilla Firefox 137: Tab Groups, Enhanced Address Bar, and More

Mozilla Firefox has rolled out its latest version, Firefox 137, on April 1, 2025. This update introduces several noteworthy features and enhancements, aimed at improving user experience and security. Below, we delve into the key updates, improvements, and potential drawbacks of this release.

New Tab Groups Feature

One of the most anticipated features in Firefox 137 is the introduction of tab groups. This functionality is designed to help users manage their tabs more efficiently by allowing them to group related tabs together. The rollout of this feature is gradual, meaning users may not see it immediately after updating. For those who want to enable tab groups sooner, a workaround is available through the experimental settings in about:config.

With tab groups, users can:

Right-click to add tabs to a new or existing group.
Edit group names and assign colors for better organization.
Drag and drop tabs to create groups quickly.
Save tab groups for future sessions, allowing users to return to their organized workspace effortlessly.

This feature can significantly enhance productivity by reducing clutter and enabling quick access to related tabs, making it easier for users to stay focused on their tasks.

Revamped Address Bar for 2025

The address bar in Firefox has received a comprehensive refresh aimed at improving usability and functionality. Key enhancements include:

Unified Search Button: A new button in the address bar allows users to switch between different search engines and modes easily.
Search Term Persistence: Instead of displaying the search engine’s URL, the address bar now shows the search term by default, aiding in refining search queries.
Secondary Action Buttons: These buttons provide quick access to frequently used Firefox features, such as printing pages directly from the address bar.
Contextual Search Mode: Firefox can detect if a webpage supports search, allowing users to execute searches directly from the page’s search options.
Keywords for Quick Access: Users can type keywords (e.g., @bookmarks, @tabs) to quickly access specific features.

This revamped address bar not only enhances user experience but also positions Firefox as a more competitive browser by integrating intuitive search capabilities.

Enhanced PDF Capabilities

Firefox 137 includes significant improvements for managing PDFs. Users can now:

Identify all links within PDFs, converting them into clickable hyperlinks.
Sign PDFs directly within the browser, eliminating the need for external applications, and save signatures for future use.

These enhancements streamline the workflow for users who frequently work with PDF documents, making Firefox a more versatile tool for professionals.

Security Improvements

Security remains a top priority with this update, as Firefox 137 addresses eight security vulnerabilities, three of which are classified as high impact. These vulnerabilities were related to memory safety and include:

Two memory safety issues.
One ‘use after free’ flaw.

Fortunately, there were no zero-day vulnerabilities exploited, which underscores Mozilla’s commitment to maintaining a secure browsing environment for its users.

Using the Address Bar as a Calculator

A neat addition to Firefox 137 is the ability to use the address bar as a calculator. Users can input simple mathematical equations directly into the address bar, and the result will be displayed in a dropdown menu, allowing for quick calculations without switching applications.

Conclusion

Overall, Firefox 137 brings a host of new features and enhancements that improve productivity, usability, and security. The introduction of tab groups, the revamped address bar, and enhanced PDF capabilities present a compelling case for both existing and new users to embrace this update. While some features may still be in a gradual rollout phase, their eventual availability will further enrich the Firefox browsing experience.