Zen Browser
Zen is an open-source browser pitched as a "calmer internet" — Firefox/Gecko-based, with split-view, workspaces, and a community mods/plugins ecosystem. Tier T3 — drawing on browser-wars-2026 (the first-party site returned an anti-bot 403 to automated fetch; summary from the roundup + the project's public description, flagged as not first-party-read).
Zen sits in the productivity/niche current alongside SigmaOS and Opera Air, but it's distinctive on two counts the spoke tracks: it is open-source and community-modded (like ladybird, a not-for-profit/community model rather than a VC product), and it is one of the few here not built on Chromium (Gecko) — so it doubles as a small vote for engine diversity. It reaches for calm/focus, not AI — the non-AI, community pole of the roster.
Re-checked 2026-09-03 (stale-queue refresh): still shipping, and shipping fast. Release 1.21.16b landed 2026-08-28 on Firefox 154.0.1; 1.21.9b earlier in the year carried a 44-CVE Firefox security patch. Nothing above needed correcting. The release cadence is itself the finding for a Gecko fork — the security-patch burden that sinks most Firefox forks is being carried, by a community project, within days of upstream.