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Preview of Known Sites

Known Sites by Marcono1234

Blocks websites which the user had not opened before.

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Blocked pageBlocked page (non-ASCII domain)
About this extension
Blocks websites which the user had not opened before.

The goal of this extension is to help protect against phishing attacks and against accidental typos when typing a URL. Users should however still be vigilant when opening links.

This is a hobby project and might not provide good protection. Do not rely on it for professional phishing protection.

Browser history and bookmarks are used to determine whether the user has opened a website before. The data is kept locally on the device, it is not transferred to any server and not used for any other purposes.
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Permissions and dataLearn more

Required permissions:

  • Read and modify bookmarks
  • Access browsing history
  • Access your data for all web sites
More information
Add-on Links
  • Homepage
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Version
1.0.4
Size
173.98 kB
Last updated
a day ago (8 Aug 2025)
Related Categories
  • Privacy & Security
Licence
MIT Licence
Version History
  • See all versions
Tags
  • security
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Release notes for 1.0.4
  • Fixed incorrect detection of IP address as host name
  • Improved handling of Incognito / Private Browsing browser windows
  • Added protection against forged extension page URLs, opened by malicious websites
  • Reduced logging of extension by default
  • Fixed error when extension encounters history entry with unsupported URL protocol
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