Zen Browser Release Notes
A clean, readable summary of the latest Zen Browser releases — plus a free AI-native alternative that keeps shipping new features every week.
Official build. Opens tabbitbrowser.com or tabbit-ai.com based on your language.
What is new in Zen Browser 1.21.5b
Security
- Patches CVE-2026-41431 and other upstream security fixes.
- Synced to the latest Firefox stable engine.
New
- Linux config now follows the XDG Base Directory Specification.
- Dragging a tab to the center offers split-above or split-below.
- Typing a URL shows a second search result for your default engine.
Fixed
- Performance and video playback on macOS 26 under heavy load.
- Startup crash for Windows users with Avast or similar security software.
- Compact-mode flicker and toolbar spacing issues.
Zen Browser release timeline
Security patch, XDG support, split-view drop options, and Windows Avast crash fix.
Command bar refinements, sidebar animation polish, and Firefox 151 sync.
Workspace switching improvements, new tab behavior tweaks, and stability fixes.
Boosts graduate to stable: per-site customization without installing a separate mod.
Security-only release synced to Firefox 150.0 with split-view and pinned-tab refinements.
Workspace tab-switching fixes, native Windows caption buttons, and compact mode tweaks.
Zen Browser vs Tabbit
Zen is great for customization and calm browsing. Tabbit adds an AI agent that works across tabs and keeps your workflow moving.
| Browser | Latest focus | AI / Agent | Active development | Platforms | Price |
|---|---|---|---|---|---|
| Tabbit | AI-native workflow + weekly releases | Agent mode + 10+ models | Active AI feature releases | macOS, Windows | Free |
| Zen Browser | Vertical tabs, workspaces, mods | No native agent | Stable maintenance releases | macOS, Windows, Linux | Free / open source |
| Arc Browser | Spaces + Arc Max chat | Arc Max (chat/summarize) | Chromium updates only | macOS, Windows, iOS | Free |
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Zen Browser Release Notes FAQ
The official changelog lives at zen-browser.app/release-notes. It lists every stable release with Security, Added, and Fixed entries.
Ready for a browser that ships AI features every week?
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