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policies.json WebsiteFilter parameter does not block indirect blocked webpages loading

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  • Last reply by Mike Kaply

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Suppose I have a "policies.json" file in the "distribution" subdirectory of my Firefox installation.

And suppose "policies.json" file contains this:

{

  "policies": {
      "WebsiteFilter": {
          "Block": [
              "*://ads.yahoo.com"
          ]
      }
  }

}

Then after restarting firefox, if I put "https://ads.yahoo.com" in the URL bar, the website is blocked and I see this: "Blocked Page", "Your organisation has blocked access to this page or web site."

BUT, if I go to "https://www.yahoo.com", (and turn on the Web Developer -> Network, (CTRL+SHIFT+E)), when this loads, it successfully manages to load: "https://ads.yahoo.com/get-user-id?ver=2&n=29657&ts=1605010286&sig=5f3e61dfa993c4da&gdpr=1&gdpr_consent=CO8qFMIO8qFMIAOACBENA9CoAP_AAH_AACiQG2Nf_X_fb3_j-_599_t0eY1f9_7_v20zjgeds-8Nyd_X_L8X_2M7vA36pr4KuR4ku3bBAQdtHOncTQmR6IlVqTPsbk2Mr7NKJ7PEilsbe2dYGH9_n9XT-ZKZ79_s___7________77______3_vpwNsAJMNS-AizEsYCSaNKoUQIQriQ6AEAFFCMLRNYQErgp2VwEfoIGAAA1ARgRAgxBRiyCAAAAAJKIgBADwQCIAiAQAAgBUgIQAEaAILACQMAgAFANCwAigCECQgyOCo5TAgIkWignkjAEoudjDCEAgAA"

which is "ads.yahoo.com" and is on the WebsiteFilter block list.

So the WebsiteFilter block is not correctly blocking loading of the URL if another URL asks it to load.

In my opinion, this is a big flaw, as one large reason to block sites in the WebsiteFilter Block list is to prevent *any* page from loading anything in the blocked list.

Therefore please can this either be fixed, or a alternative "Block" suboption provided under "WebsiteFilter" that will block direct (given in URL bar) or indirect (another page trying to load it) loads ?

I'm using firefox 82.0.2 (64 bit) on Windows

Suppose I have a "policies.json" file in the "distribution" subdirectory of my Firefox installation. And suppose "policies.json" file contains this: { "policies": { "WebsiteFilter": { "Block": [ "*://ads.yahoo.com" ] } } } Then after restarting firefox, if I put "https://ads.yahoo.com" in the URL bar, the website is blocked and I see this: "Blocked Page", "Your organisation has blocked access to this page or web site." BUT, if I go to "https://www.yahoo.com", (and turn on the Web Developer -> Network, (CTRL+SHIFT+E)), when this loads, it successfully manages to load: "https://ads.yahoo.com/get-user-id?ver=2&n=29657&ts=1605010286&sig=5f3e61dfa993c4da&gdpr=1&gdpr_consent=CO8qFMIO8qFMIAOACBENA9CoAP_AAH_AACiQG2Nf_X_fb3_j-_599_t0eY1f9_7_v20zjgeds-8Nyd_X_L8X_2M7vA36pr4KuR4ku3bBAQdtHOncTQmR6IlVqTPsbk2Mr7NKJ7PEilsbe2dYGH9_n9XT-ZKZ79_s___7________77______3_vpwNsAJMNS-AizEsYCSaNKoUQIQriQ6AEAFFCMLRNYQErgp2VwEfoIGAAA1ARgRAgxBRiyCAAAAAJKIgBADwQCIAiAQAAgBUgIQAEaAILACQMAgAFANCwAigCECQgyOCo5TAgIkWignkjAEoudjDCEAgAA" which is "ads.yahoo.com" and is on the WebsiteFilter block list. So the WebsiteFilter block is not correctly blocking loading of the URL if another URL asks it to load. In my opinion, this is a big flaw, as one large reason to block sites in the WebsiteFilter Block list is to prevent *any* page from loading anything in the blocked list. Therefore please can this either be fixed, or a alternative "Block" suboption provided under "WebsiteFilter" that will block direct (given in URL bar) or indirect (another page trying to load it) loads ? I'm using firefox 82.0.2 (64 bit) on Windows

Chosen solution

This is working as designed. The website filter is not designed to block all requests. It's designed to block top level loads of websites.

You should use an ad blocker or some other software for more thorough blocking.

That being said, though, there is a rewrite of the filter coming in the next Firefox that might actually block this depending on how it is loaded.

You might try Firefox Beta and see if it behaves any differently.

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Chosen Solution

This is working as designed. The website filter is not designed to block all requests. It's designed to block top level loads of websites.

You should use an ad blocker or some other software for more thorough blocking.

That being said, though, there is a rewrite of the filter coming in the next Firefox that might actually block this depending on how it is loaded.

You might try Firefox Beta and see if it behaves any differently.