Simply block sites based on a blacklist.
Enter domains to be blocked, include only domains.
Ex: news.ycombinator.com
INFO: This addon does not stop requests to blocked domains, only stops the user from viewing the content.

FBlock: Block Sites with a Firefox Add-on
FBlock is a Firefox add-on that enables you to easily block specific websites using a blacklist. It prevents users from accessing the content on these blocked domains without stopping the requests to them.
Add-on stats
Manifest V2
Firefox on Android: Yes
Permissions:
- storage
Size: 10.71K
Email: ru*****@outlook.com
Ranking
Other platforms
Not available on Chrome
Not available on Android
Not available on Edge
Add-on safety
Risk impact
FBlock requires a few sensitive permissions. 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.
- High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
- Low ******* ****** ** *** ********* ********
Risk likelihood
FBlock is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.
Risk likelihood analysis details
- High This extension has low user count. Unpopular extensions may not be stable or safe.
- Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
- Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
Upgrade to see full risk analysis details
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