ThreeTabs: a browser that only lets you open three tabs
Mohamad Almousli ยท 2026-10-04 ยท 2 min read
Twenty open tabs feel like productivity. They're mostly a pile of things you meant to get to. ThreeTabs is a small browser extension that gives you three tabs by default and politely refuses to open a fourth.
Why a hard limit
Tab hoarding is a deferral habit: opening something is free, deciding about it is not. A hard cap flips that. To open a new page you have to finish or close an old one, which forces the small decisions you'd otherwise postpone forever.
Reminders and tab-groupers organize the pile. A limit stops it from forming.
How it works
The limit is 3 by default and adjustable from 1 to 50. When you hit it, new tabs and windows are blocked. Optionally the blocked link opens in the tab you came from instead, so nothing is lost. You can count across all windows or per window.
It never closes tabs you already have open, and the settings page always opens, even when you're over the limit. The toolbar icon stays quiet: no numbers, just a popup showing your slots and a counter of blocked tabs.
Privacy and install
No analytics, no tracking, no ads. It asks for three permissions: tabs (to count them and close the extra one), storage (to keep your settings locally) and alarms (for an optional daily check for a new GitHub release, which you can turn off โ the only network request it makes).
It works on Chrome, Edge, Brave, Opera, Vivaldi and Firefox (Manifest V3), is MIT-licensed, and can be loaded from source today.