Cleo is a lightning-fast, privacy-focused, and highly customizable New Tab extension designed for Chromium and Firefox-based browsers (Chrome, Edge, Brave, Vivaldi, Firefox, etc.). It transforms the standard browser startup screen into a clean, distraction-free dashboard equipped with essential productivity tools, smart shortcut management, and deep aesthetic controls.
Switch between high-contrast presets or adapt the UI dynamically to any uploaded wallpaper.
- Custom Intervals: Adjust focus sessions (25–120 min) and break intervals (5–30 min) with real-time numeric and slider controls.
- Persistent Background Timing: Operates via Manifest V3 alarms and service workers to track sessions even when tabs are closed.
- Audio-Visual Notifications: Native desktop notifications alert you when sessions start, pause, or complete.
- Flexible UI: Position the timer in the top-left or top-right corner, toggle borders, and choose between custom, accent-matched, or high-contrast monochrome styles.
- 10 Built-In Search Providers: Google, Google Web (Clean / UDM=14), DuckDuckGo, Brave, Startpage, Kagi, Bing, Yahoo, Qwant, and Ecosia.
- Instant Engine Switcher: Rapidly toggle engines directly from the search bar dropdown without entering settings.
- Smart URL Navigation: Detects valid domain structures and routes directly to URLs, bypassing standard search redirects.
- Dynamic Greetings: Displays contextual, time-aware greetings and clean search placeholders.
- Hybrid Data Sources: Switch between your browser's most visited sites (
topSites) or a fully custom curated bookmark grid. - Drag-and-Drop Reordering: Reorder shortcut tiles with fluid drag interactions.
- Pinning & Menu Actions: Pin essential shortcuts to keep them fixed at the front of the grid; edit or delete items on the fly.
- Smart Favicon Contrast Inversion: Built-in canvas contrast engine analyzes favicon pixel luminance to intelligently invert dark-on-dark or light-on-light monochromatic icons while leaving multi-colored logos untouched.
- Accidental Deletion Recovery: Built-in undo toasts let you restore removed shortcuts immediately.
- Configurable Density: Adjust grid sizes from 1 to 5 rows (10 to 50 max shortcuts) with optional text labels.
- One-Click Presets: Instant access to curated themes: Cleo Default, Midnight Slate, Warm Obsidian, and OLED Void.
- Custom Backgrounds & Wallpapers: Set solid hex colors or upload local image wallpapers with automatic palette detection.
- Global Master Controls: Adjust corner roundness (0–50px), widget opacity (0–100%), and frosted glass blur (
backdrop-filter) across the entire interface. - Typography Selector: Choose across clean Sans-Serif, elegant Serif, Monospace, or System Default font stacks without page reloads.
- Adaptive Clock & Date: 12-hour/24-hour modes, optional seconds display, four date format conventions, and dynamic complementary color calculations.
- Scrollbar Customization: Set visibility to persistent or hover-only, with automatic, accent, or custom color modes.
- Layout Lock: One-click lock toggle prevents accidental drag movements or layout changes.
- In-Panel Full-Text Search: Find setting toggles and controls using a real-time search filter with keyword highlighting and match navigation.
- Zero-FOUC Startup: Preload engine initializes CSS variables and layout states synchronously from storage before the DOM renders, preventing screen flashes.
- Clean-Slate Backup & Restore: Export all dashboard configurations, shortcuts, and timers to a single JSON file, or restore backups cleanly without leaving legacy configuration artifacts.
| Parameter | Specification |
|---|---|
| Manifest Version | Manifest V3 |
| Frameworks / Libraries | 100% Vanilla ES6+ JavaScript, CSS3, HTML5 (0 external runtime dependencies) |
| Storage Architecture | Synchronous localStorage cache backed by chrome.storage.local persistence |
| Browser Compatibility | Google Chrome, Microsoft Edge, Brave, Opera, Vivaldi, Mozilla Firefox (v109+) |
| Rendering Strategy | Hardware-accelerated CSS GPU compositing (transform, opacity, backdrop-filter) |
| Network Requests | 0 external telemetry, analytics, or CDN calls; operates 100% offline |
Cleo is engineered to operate strictly within the client sandbox:
- No Remote Telemetry: Cleo does not collect, log, or transmit personal data, browsing history, or search queries.
- Local Data Execution: All configurations, custom shortcuts, and timer states remain stored exclusively inside your browser's local sandbox database.
- Direct Search Routing: Outgoing search queries route straight from your client to your selected search provider with zero intermediary proxies.




