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Preview of TabFence: Time Based Site Blocker

TabFence: Time Based Site Blocker by KuduzKunduz

Schedule-based site blocker for deep work and focus — block distracting websites during your focus hours

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Extension Metadata

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HomepageNew rulesSettingsWith rule
About this extension
DeepFocus: Site Blocker is a privacy-first, schedule-based website blocker designed for knowledge workers, students, and anyone who wants to reclaim their focus time.

How It Works
  • Create Rules: Define which sites to block (e.g., youtube.com, twitter.com, instagram.com)
  • Set Schedules: Choose specific time ranges (e.g., 09:00–12:00 Mon–Fri) or daily time budgets (e.g., 30 minutes/day)
  • Stay Focused: When a rule is active, blocked sites redirect to a friendly reminder page with a countdown
  • Global Toggle: Turn all protection on/off with one click from the popup dashboard

Key Features
  • Two Blocking Modes:
  • Time Range: Block sites during specific hours and days
  • Daily Budget: Allow limited time per day (e.g., 30 min for Twitter) — once exhausted, the site is blocked until midnight
  • Midnight Countdown: For budget-exceeded rules, the blocked page shows a live countdown to reset
  • Dark Mode & Light Mode: Choose Light, Dark, or follow your system theme
  • Bilingual UI: Full Turkish (Türkçe) and English support
  • 100% Local: All data stays on your device — no accounts, no cloud, no tracking
  • No Ads, No Premium: Completely free with no paywalls

Privacy

DeepFocus: Site Blocker does not collect, transmit, or share any personal data. All settings and usage data are stored locally in your browser using storage.local. No analytics, no crash reporting, no third-party services. No network requests are made to external servers.

Required Permissions

| Permission | Why It's Needed |
|-----------|----------------|
| storage | Save your rules and settings locally |
| alarms | Schedule rule activation/deactivation |
| tabs | Redirect blocked tabs to the reminder page |
| webNavigation | Detect navigation to blocked sites |
| <all_urls> | Block sites on any domain you configure (required because you choose which sites to block) |

Browser Compatibility
  • Firefox Desktop 142.0+
  • Manifest V3 WebExtension
  • Private browsing compatible

Languages
  • English 🇬🇧
  • Turkish (Türkçe) 🇹🇷

Version History
  • 1.0.0 — Initial public release with Time Range blocking, Daily Budget blocking, Dark Mode, Bilingual UI

Screenshots
  1. Popup dashboard showing active rules
  2. Rule creation page with Time Range / Daily Budget modes
  3. Blocked page with countdown timer
  4. Rules list with edit/delete options
  5. Settings page (language & theme)

Support
  • Email: aliveliemmi@outlook.com

Categories
  • Productivity
  • Privacy & Security
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access browser activity during navigation

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
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Version
2.0.0
Size
220.88 KB
Last updated
5 days ago (Jun 13, 2026)
Related Categories
  • Privacy & Security
  • Alerts & Updates
License
All Rights Reserved
Version History
  • See all versions
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