Zen Browser 1.20.1b drops as a stable update built on Firefox 151.0.2, bringing routine security patches alongside some genuinely useful tweaks. The standout addition lets you type New Boost straight into the address bar to instantly configure site-specific rules without digging through nested menus. Several annoying bugs finally get squashed, including that pesky tab duplication glitch when hitting u and the fullscreen video controls that kept vanishing off screen on certain displays. macOS users also get a fix for smart card certificate loading, making this a solid maintenance release worth installing if you actually use Zen as your daily driver.

Zen Browser 1.20.1b Released with Firefox 151 Base, New Boost Shortcut, and Critical Fixes

Zen Browser 1.20.1b arrives as a stable update that brings the browser engine up to Firefox 151.0.2 while patching several usability issues. The release introduces a faster method for creating site-specific boosts directly from the address bar and resolves bugs involving tab duplication, fullscreen video controls, and macOS certificate handling. Users looking for a smoother experience with Zen's tiling interface should consider updating now.

Firefox 151.0.2 Engine Update

The underlying engine moves to Firefox 151.0.2, which brings the latest security patches and stability improvements from Mozilla's main branch. This ensures Zen stays compatible with modern web standards without requiring a major version jump. The update maintains Zen's unique tiling features while benefiting from the core browser refinements included in the Firefox release cycle.

Quick Boost Creation via URL Bar

Creating site-specific boosts just became more efficient with a new shortcut option. Users can now type New Boost directly into the URL bar to instantly generate a boost configuration for the current website. This removes the need to navigate through menus or settings panels when tweaking how Zen handles specific domains. The feature integrates seamlessly with the existing boost system, allowing quick adjustments to behavior like autoplay policies or script blocking without interrupting workflow.

Zen Browser 1.20.1b Bug Fixes and Stability Improvements

Several reported issues get resolved in this release. A persistent bug causing tabs to duplicate when pressing the 'u' key has been addressed. This issue likely stemmed from a shortcut collision that frustrated users trying to use navigation commands or custom bindings. Video playback problems during fullscreen mode also see improvements, as controls no longer disappear behind screen edges on certain display configurations. macOS users benefit from fixes related to smart card and security key certificate loading, which previously failed to load automatically in some scenarios. Boosts themselves receive reliability tweaks for sites that were not responding correctly before the update.

Release Release build - 1.20.1b (2026-05-27)

Zen Stable Release New Features Updated to Firefox 151.0.2 You can now type New Boost in the urlbar to quickly create a new boost for the current site! Fixes Fixed pressing u duplicating tabs. (...

Release Release build - 1.20.1b (2026-05-27) · zen-browser/desktop

Grab the update when ready and keep Zen running smooth.