Zen Browser Updates & Release Notes

If you encounter any issues, please report them on the issues page.

Security

Various security fixes.

Fixed

• Fixed various animation, urlbar and UI performance issues.
• Fixed Library media tab requesting onedrive to download all files. (Bug gh-15888)
• Fixed unwanted label next to the search icon in urlbar. (Bug gh-14856)
• Fixed Avahi access so CUPS printers are listed in flatpak sandbox. (Bug gh-9651)
• Fixed various memory leak issues. (Bug gh-15954)
• Fixed a crash that could occur while Zen loaded website icons (favicons).
• Fixed menus such as List all tabs, Settings, etc being hard to read with a Windows High Contrast theme. Menu background and text colors now follow the Background and Text colors chosen for a custom contrast theme in Windows Settings.
• Other bug fixes and improvements.

Added

• Updated Firefox to 158.0
• Added a --space option to the command line interface.
• Library will now show a 'Open in Folder' option and download speed when hovering over the toolbar icon.
• Zen now creates more accessible PDFs when saving a page as PDF, and when printing on Linux and macOS. This also fixes a variety of PDF rendering issues, such as missing math symbols.

Change

• Space routing regex will now match URLs as case-insensitive.
• Library's widget hover list will now only display recently downloaded files.
• Zen no longer rounds scroll positions to whole screen pixels. Scrolling is now smoother and more precise, especially on high-resolution displays or when a page is zoomed.

Fixed

• Changed session backup file names to use local dates (Bug gh-15806)
• Fixed the library getting stuck after opening and closing it quickly (Bug gh-15833)
• Fixed blocked/unsafe downloads not having the choice to be opened or saved. (Bug gh-15809)
• Fixed moving multiple tabs to new window irrecoverably loses unloaded tabs. (Bug gh-15810)
• Fixed the sidebar having too much minimum width when they are aligned to the right. (Bug gh-15794)
• Fixed HEIC media being listed in the media tab but do not render correctly. (Bug gh-15778)
• Fixed space-assigned bookmarks not being saved anymore. (Bug gh-12721)
• Fixed a memory leak issue on startup.
• Other bug fixes and improvements.

Added

• Added an 'open library' command to the command palette.
• You can now right-click the media tab in the Library to disable it.

Security

Various security fixes.

Fixed

Fixed transparent sidebars having low opacity.

Fixed downloads failing on macOS when Firefox is set to ask where to save files but doesn't have permission to access the Downloads folder.

Other bug fixes and improvements.

Added

Updated to Firefox 157.0.1

Added an option in the Library to filter closed tabs instead of history entries.

A keyboard shortcut (opt/alt + shift + L) has been added to quickly open the Library.

'Clear all downloads' and 'Clear history' options have been added to the Library by right clicking on the respective section tabs.

Security

Various security fixes.

Fixed

Significant performance improvements on startups/new windows when there are lots of tabs open.

Certain icon animations like the boost indicator or musical notes on the sidebar are now more performant. (Bug gh-15299)

Fixed status panel and glance controls not using the correct theme colors. (Bug gh-15280)

Fixed some HDR videos encoded in 8-bit color formats looking dull and gray on Windows instead of displaying in HDR.

Improved audio and video synchronization when repeatedly changing the playback speed of videos, for example on YouTube.

Fixed an issue on Windows where making a video full screen would leave the Windows taskbar showing over the video.

Added

Introducing Library! A better place to organize and access your history, media, downloads, spaces and more.

You can now resize the sidebar even when its hidden. If the sidebar is resized too small, it will automatically hide itself.

Updated to Firefox 157.0

WebRTC video calls can now use hardware AV1 decoding on devices that support it, instead of always decoding AV1 video in software.

Change

When a link gets routed to a specific space, it will prioritize the window that has that space open.

Some elements like the sidebar and the command bar now appear with blur effects.

On MacOS, buttons at the bottom of the sidebar now appear larger.

Swiping to the right on the last space will now try to create a new space. (This can be disabled via zen.workspaces.swipe-actions set to false in about:config)

When the sidebar is at the right, the buttons at the bottom are now reversed.

Fixed

Fixed Zen leaking system handles on Windows as content processes were started and stopped.

Fixed context menu actions on the urlbar not working. (Bug gh-15437)

Fixed overflow-extension order in single toolbar mode. (Bug gh-15419)

Fixed not being able to install add-ons while in compact mode. (Bug gh-15445)

Fixed Zen windows on macOS 27 immediately returning to maximized after being restored by double-clicking the title bar.

Fixed Other bug fixes and improvements.

Added

Updated to Firefox 156.0.1

The command bar now allows you to search through tabs and folders more efficiently.

If you encounter any issues, please report them on the issues page.

Security

Various security fixes.

Fixed

Fixed high-sample-rate FLAC audio in MP4 failing to play on certain video sites.
Fixed subtitles not appearing in the Picture-in-Picture window when they are turned on in the video player after the window has already opened.
Fixed the find bar becoming permanently unavailable in a tab after reversing the panes in Split View.
Fixed some sites failing to load when DNS over HTTPS is enabled and the site does not support HTTPS.
Fixed an issue on Windows where Zen could block an auto-hiding taskbar from showing.
Fixed the sidebar not hiding if the urlbar is open when compact mode is enabled. (Bug gh-13196)
Fixed an issue where cross-space tab routing would freeze the browser under certain conditions. (Bug gh-14171)
Fixed cross-device sync losing certain tabs if they are created too quickly (Bug gh-15380)
Fixed certain issues related to live folders appearing as active even when they are no tabs showing in them.
Other bug fixes and improvements.

Added

Updated to Firefox 156.0
Zen on macOS can now be set to open automatically when the computer starts up, from the Startup section of Settings.
Added the following actions to the command bar: 'Expand current view', 'New space', 'Reopen closed tab', 'Duplicate tab', 'Reset pinned tab'.

Change

Zen's built-in PDF viewer now starts up to 45% faster.
Improved memory and CPU usage when Zen displays large JPEG images scaled down to fit a page.
On Windows devices with ARM64 processors, WebRTC video calls may now use hardware H264 decoding instead of falling back to software.
Live Folders will now ignore archived issues and pull requests.
Improved the look and feel of drag-and-drop interactions for tabs. Specially on MacOS, where the drag-and-drop behavior is now done natively.
Folders will now fully-expand if all tabs within them are visible. Folder animations has also been improved for smoother transitions.

Fixed

Noticeably improved performance and battery usage while scrolling, and playing videos.

Other bug fixes and improvements.

Added

You now have the option to sync normal tabs across devices along with your Spaces, Folders, and other data. This can be enabled in Settings > Sync > Sync your Spaces across devices.

You can now share Spaces, folders and split views to other Zen users and non-Zen users via a shareable link. This can be found in the context menu of a Space, folder or split view.

The on-boarding experience will now ask if you want to enable ad blocking, which will install uBlock Origin for enhanced privacy and security.

This release includes a major new feature to sync your Spaces across devices using your Mozilla account! Please note that the first time this feature is enabled, it will merge both your local and cloud Spaces.

If you encounter any issues, please report them on the issues page.

Security

Various security fixes.

Fixed

Fixed live folders for GitHub issues not working with the new GitHub UI
Fixed Zen preventing Linux systems from going to sleep after a long browsing session.
Fixed arrow-key and Page Up/Down scrolling not working on some pages with embedded content from other sites.
Fixed live audio streams such as internet radio stopping when playing in the background.

Other bug fixes and improvements.

Added

Updated to Firefox 155.0 and 155.0.1

Added

By using your Mozilla account, you can now sync your Spaces, Folders, Tabs, and much more between devices! This can be enabled in Settings > Sync > Sync your Spaces across devices.

Added

The chrome UI now has a better look and feel, implementing squircles and other design elements to make it more visually appealing.

Added

A new on-boarding experience has been added to help new users get started with the browser and its features.

Added

Creating a new Space is now faster and requires less animation wait time, making the process more efficient.

Added

Containers can now be reordered in Settings, and the new order is used wherever containers are listed.

Change

Font size has been increased for the sidebar text, making it easier to read and navigate through tabs and spaces.

Change

Zen now uses firefox-portal-detection.com instead of detectportal.firefox.com to detect captive portals and check network connectivity, so network allowlists referencing the old domain need updating.

Change

PDFs smaller than the paper size can now be enlarged to fill the sheet when printing, by setting the scale above 100%.

Fixed

Improved on session store performance, lowering CPU usage spikes and disk usage when storing the session (Bug gh-14990)

Fixed duplicate separator on tab context menu (Bug gh-15031)

Fixed minimizing PiP window failing to collapse into the sidebar (Bug gh-14710)

Fixed slower access to saved passwords and unexpected Primary Password prompts caused by recent changes to password storage.

Fixed an issue where addresses were failing to autofill on some sites.

Other bug fixes and improvements.

Added

Update Firefox version to 154.0.1

If you encounter any issues, please report them on the issues page.

Security

Various security fixes.

Fixed

Improved battery life on MacOS when using vibrancy effects

Improved performance of session restore, having spikes of CPU usage every time the session is stored into disk (Bug gh-14990)

Fix multiple glance tabs when joining tabs (Bug gh-14975)

Improved rendering performance on MacOS and memory leaks when using WebRTC (Bug gh-9649)

Fixed an issue on macOS where closing a browser window could leave behind an invisible window that continued to capture mouse clicks over the area where it used to be.

Fixed an issue on Windows where an auto-hiding taskbar would not appear until the Zen window had been minimized and restored after launch.

Fixed an issue where the Windows taskbar would appear in front of a full screen Picture-in-Picture window.

Fixed PDF documents not being scaled correctly in print preview when the Fit to Page Width option is used.

Other bug fixes and improvements.

Added

Update Firefox version to 154.0

Local Zen profile backups are now available on macOS in addition to Windows and Linux, and backups can be restored across all three platforms.

Sites can now be exempted from having their cookies and site data cleared on shutdown without also being exempted from tracking protection and other cookie restrictions.

The full-page Translations feature now translates content.

The full-page Translations feature now runs language identification on all page loads, resulting in an improved experience for offering translations to users.

Performing a hard reload on a page (holding Shift while clicking the Refresh button) now also clears and updates its cached favicons.

Change

Improved performance on all systems and benchmarks by using a different memory allocator

Video seeking is now significantly faster on all operating systems, making it quicker to jump to a point in a video.

Enabled webrender compositor on Linux, improving performance and reducing power usage on Linux systems that support it.

Text selected in a PDF is now highlighted the same way as text on a web page, and the highlight color follows operating system settings such as high-contrast mode.

Known

Following recent changes to Zen's password storage, some users may experience slower performance when Zen accesses saved passwords. Users with a Primary Password enabled may also see unexpected password prompts, such as when starting Zen or opening certain content.

Fixed

Fixes issue setting keybinds with shift + digit or symbol (Bug gh-9918)

Fix closing split tab in one window changing focus of other windows (Bug gh-13761)

Fixed audio and video failing to play, or hanging when seeking, on websites that load media from a Blob URL.

Other bug fixes and improvements.

Added

Updated Firefox to 153.0.3

You can now filter draft GitHub pull requests in live folders.

Compact mode now tracks your mouse even after it leaves the window, the sidebar stays open while your cursor lingers near the window's edge and only tucks away once you move further out. This only changed for Windows and MacOS, Linux is still the same as before.

You can now move the window by dragging empty space in the top part of a webpage, with native snapping and tiling, just like dragging the titlebar. Links, buttons, and other interactive elements still work as usual.

You can now have multiple media controls in the sidebar, allowing you to control multiple media sources at once.

Improved startup performance and feeling

Fixed

Various performance fixes, energy consumption improvements, RTX Super Resolution not working, and HDR video playback not working on Windows.

NOTE: This might need a restart to take effect (Bug gh-14292)

• Fixed extra divider when urlbar has no results (Bug gh-14717)
• Fix boost applying wrong size override (Bug gh-14461)
• Fixed crashes/hangs when creating new spaces (Bug gh-14713)
• Fixed non-tab drags allowing to switch Spaces (Bug gh-14724)
• Fixed essential tab reordering not working at maximum capacity (Bug gh-14726)
• Fixed compact sidebar activation at right screen edge (Bug gh-14409)
• Other bug fixes and improvements.

Added

Updated Firefox to 153.0.1