I've been building Firefox extensions for the past several months. Here's where things stand — 10 extensions live on AMO, all free, all no-account, all no-server.
This isn't a launch post. It's a snapshot: what I built, why, and what I learned from each one.
1. Weather & Clock Dashboard
The first one I shipped. Replaces the new tab with live weather (via wttr.in — no API key needed), configurable world clocks, and a search bar.
The lesson from this one: a new tab extension lives or dies on first load time. I spent a lot of time on the loading state so it doesn't flash blank before weather loads.
2. NightOwl — Dark Mode
Automatically switches dark mode on at sunset and off at sunrise. Per-site overrides for websites that break with CSS inversion.
Dark mode extensions are a crowded space. What differentiates NightOwl: it's automatic. No manual toggle, no remembering to switch. Set your location once and forget it.
3. Voice Notes — Audio Recorder
Record voice memos in the browser. Uses MediaRecorder API, stores everything in IndexedDB. Zero server communication — your recordings never leave your device.
This one resonated most with users concerned about privacy. If you don't trust cloud voice memo apps with your microphone, this is the alternative.
4. Tab Manager & Session Saver
Save your current tabs as a named session, restore them later. Also works as a quick bookmark manager.
The design philosophy: "save" rather than "organize." I don't want to manage tabs — I want to close them without losing them.
5. News & Widget Dashboard
New tab with RSS news feeds, weather, notes, and bookmarks. Configurable panels — show what you want, hide what you don't.
The challenge: RSS is dead for most people but still useful for following specific sources without an algorithm. This extension makes it accessible.
6. Daily Planner & To-Do List
Task list on every new tab. Live clock, motivational quote, built-in search. Drag-and-drop reorder, priorities, deadlines.
I wanted something between "empty browser default tab" and "full project management software." This fills that gap.
7. Stock Market & Finance Dashboard
Live stock quotes, crypto prices, market movers on every new tab. Uses Yahoo Finance API and free crypto endpoints — no API key.
The technical challenge: financial data APIs are expensive or key-restricted. Finding endpoints that work in a browser extension without a key took iteration.
8. Quick Calculator & Unit Converter
Calculator, unit conversions (length, weight, temperature, currency), and a quick search bar on the new tab.
Built this because I was opening Google just to convert units. A new tab calculator saves the round-trip.
9. Habit Tracker — New Tab
Monthly habit grid on every new tab. Mark off daily habits, see your streak at a glance. Multiple themes (journal, night, ocean, rose).
The habit tracker market is saturated with apps that require accounts. The browser version removes all friction: it's there every time you open a tab.
10. Speed Dial & Tools Hub
Speed dial bookmarks, a notepad, a calculator, and recent history on the new tab. Everything in one place.
Speed dial was a Firefox feature from the Opera era that never made it into the core browser. This brings it back with modern UX.
Common threads
Looking at all 10, a few patterns emerge:
No server, no account. Every one of these works offline and stores data locally. I didn't want to maintain backend infrastructure or handle user data.
New tab as the surface. Most use the new tab as the entry point. It's free real estate — you open it constantly, so ambient information there has real utility.
Free APIs where possible. wttr.in for weather, Yahoo Finance for stocks, free crypto endpoints. All public, no key rotation.
Single purpose. Each extension does one thing. I didn't build mega-extensions with 20 features.
All 10 extensions are free and open to install on Firefox Add-ons. Published under account weatherclockdash.
