From MozillaZine Knowledge Base



Firefox incorporates the Google Safe Browsing extension in its own Phishing Protection feature to detect and warn users of phishy web sites.

When a site is classified as safe or unsafe, a partial hash is generated of a fragment of the URL. This can be compared against the remote database to return a complete hash and extra metadata. When the hash is sent, a number of random hashes are sent along with it to obscure the “real” URL. This preference determines how many random entries are sent.

Possible values and their effects

A non-negative integer indicating the number of random entries to send with the actual hash when comparing a URL against the remote database. Default value is 4.


First checked in

2008-02-26 by Dave Camp

Has an effect in

  • Firefox (nightly builds since 2008-02-26)

Related bugs

Related preferences

External links