Block Site
A customizable, password-protected website blocker and redirector.
Block Site - Customizable Website Blocker and Redirector Add-on for Firefox
'Block Site' is a Firefox extension providing control over website access. It allows you to block unwanted domains, use wildcard or regex matching, utilize reverse mode to limit access only to selected sites, and redirect blocked hostnames to new destinations. Furthermore, it protects against data leakage by preventing certain hostnames from capturing your network activity. Additional features include timed blocking, custom messages on blocked pages, aut0-closure of blocked tabs, killing pop-ups, and configurable pause and resume options.
Add-on stats
Manifest V2
By: Ray
Rating: 3.92 
1 new ratings
(481)
Weekly download count: 2,425
Firefox on Android: No
Permissions:
- activeTab
- storage
- notifications
- alarms
- contextMenus
- declarativeNetRequestWithHostAccess
- <all_urls>
- webRequest
- webRequestBlocking
Size: 174.83K
URLs: Website
Full description: See detailed description
Ranking
# 255 ▲ 1
Other platforms
Not available on Chrome
Not available on Android
User reviews
These summaries are automatically generated weekly using AI based on recent user reviews.
Firefox Browser Add-ons does not verify user reviews, so some user reviews may be inaccurate,
spammy, or outdated. Pros
- Works effectively to block sites
- Simple and easy to use interface
- Customizable blocking rules
- Leaves the user focused and reduces distractions
Cons
- Corrupts open tabs when blocking sites
- Confusing user interface and settings
- Doesn't always block sites as intended
- Difficult to set up and use initially
- UI issues, particularly for non-English speakers
Most mentioned
- Corruption of open tabs
- Difficulty in understanding and using the extension
- Inconsistent performance in blocking websites
User reviews
by Drafer, 2025-03-08
used to work some (long) time ago, now it doesn't
by Firefox user 17472807, 2025-03-03
Works perfectly, simple and easy to use. The only downside being that when you have for example, 10 tabs with different YouTube URLs and then you want to block YouTube, all the tabs lose their url and become YouTube, which means that after unblocking YouTube, all my saved tabs become the default main page.
by 99xPotions, 2025-02-28
Add-on safety
Risk impact
Block Site requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.
Risk impact analysis details
- Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
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Risk likelihood
We don't have sufficient data to confidently determine the risk likelihood of Block Site. Use it at your own risk.
Risk likelihood analysis details
- Medium This extension has medium user count. Unpopular extensions may not be stable or safe.
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