Firefox 133 is out with advanced protection against tracking

The team behind he Firefox browser introduced Firefox 133. It comes with much improved Enhanced Tracking Protection, automatic PiP enabled for more sites, more accessible tabs from other devices, accelerated 2D canvas, and more.

What's new in Firefox 133

Enhanced Tracking Protection improvements

In the strict mode of ETP Firerox 133 now implements protection against tracking using redirects (Bounce Tracking Protection). The Bounce Tracking Protection mechanism allows you to catch activity specific to tracking via redirects and periodically clear Cookies and locally stored data used for tracking.

Unlike the previously available "Cookie Purging" mode, where cleaning was based on a list of known trackers, the new implementation uses heuristics that allows it to identify new tracker sites by analyzing behavior after a redirect.

The essence of the redirect-based tracking method is that the tracker code first redirects the user to its site, and then transfers them to the target page, which allows the tracker to save Cookies and data in local storage in connection with its site.

Saving data after switching to another site allows it to bypass previously implemented Firefox methods of blocking cross-site operations. Because the intermediate page opens outside the context of another site, the tracker can freely install tracking Cookies on such a page.

User interface improvements

An new item has been added to the menu with a list of open tabs (the one that opens via the button in the upper right corner). It allows you to show a list of tabs from your other devices right in the sidebar.

Automatic Picture-in-Picture

The browser now support more sites in the automatic picture-in-picture mode. It will open a PiP flyout after switching from the tab on which the video is shown to another tab.

Other changes

• If there is information about the time on the server, the value of the "expire" attribute is adjusted taking into account the difference between the local time and the time on the server. If the time on the local system is set to the future, then the Cookie continues to be considered valid according to the server time.
• Windows platform builds have GPU acceleration enabled for the Canvas2D API .
• The Fetch API has added support for a " keepalive " parameter that keeps the connections associated with an HTTP request alive after the page is closed or navigated to another page, allowing you to use the fetch() call to send analytics at the end of a session even if the page has already been closed.
• Firefox version for Android now enables desktop mode by default for devices with large screens. You can change the behavior in the "Site settings" section.
• When copying text to the clipboard from a page in private browsing mode, the copied content is now treated as containing confidential data (the user is prompted with a warning).

In addition to new features and bug fixes, Firefox 133 fixes 18 vulnerabilities. Three vulnerabilities are marked as dangerous. Four vulnerabilities are caused by improper work with memory, such as buffer overflows and access to already released memory areas. These issues could potentially lead to the execution of malicious code when opening specially designed pages.

Firefox 134, now in beta, adds support for additional touchpad gestures (such as two-finger tap to pause inert scrolling) to Linux builds, and adds support for hardware decoding of HEVC (H.265) video on Windows.

Download Firefox

Alternatively, you can download the installers here: https://releases.mozilla.org/pub/firefox/releases/133.0/. Choose the browser compatible with your OS, language, and platform from there. The files are sorted into subdirectories by platform and UI language, and they include complete (offline) installer packages.

Linux users should use the OS' package manager to get the latest version available for the distro. E.g. in Ubuntu/Mint with the official mozillateam PPA connected, you can run the apt update && apt install firefox command in a root terminal.

The official release notes are here: https://www.mozilla.org/en-US/firefox/133.0/releasenotes/.