I understand that feature was removed because it was unmaintained and probably not working properly. One of the Developers working on the changes wrote

The functionality was unmaintained, bogus and not really nice to use on today's Web. Yes, it would be better if implemented in an add-on, so someone could take care of it properly and interested users in the community could drive its future better. Honestly today we have better replacements to protect privacy, you can control third-party cookies and tracking protection can be enabled through privacy.trackingprotection.enabled (in newer versions directly from Options / Privacy), plus there's a bunch of nicely made add-ons that can block any kind of contents on AMO. Sticking to a dialog that pops up every other second and can easily break website functionality, is just not being realistic, Mozilla is still fighting for users privacy (tracking protection is a clear sign of that), but the tools used to do that should be on par with the current Web and should have the due quality, imo. {_{bug606655#c50} )

You may also be interested in this

• https://sporadicdispatches.blogspot.co.uk/2015/11/better-living-through-tracking.html

And the following addons

• Privacy Badger 1.8.1 https://addons.mozilla.org/firefox/addon/privacy-badger-firefox/
• Cookie Controller 5.5 https://addons.mozilla.org/firefox/addon/cookie-controller/
• uBlock Origin 1.9.6 https://addons.mozilla.org/firefox/addon/ublock-origin/
• Ghostery 6.3.2 https://addons.mozilla.org/en-GB/firefox/addon/ghostery

You are free to use an unsupported unsafe and insecure version of Firefox if you wish.

• Install an older version of Firefox

You may wish to mitigate risks by using a VM &/or having a well rehearsed bare metal restore policy.

• See also https://www.mozilla.org/security/known-vulnerabilities/firefox/

John99 said

I understand that feature was removed because it was unmaintained and probably not working properly. One of the Developers working on the changes wrote

The functionality was unmaintained, bogus and not really nice to use on today's Web. Yes, it would be better if implemented in an add-on, so someone could take care of it properly and interested users in the community could drive its future better. Honestly today we have better replacements to protect privacy, you can control third-party cookies and tracking protection can be enabled through privacy.trackingprotection.enabled (in newer versions directly from Options / Privacy), plus there's a bunch of nicely made add-ons that can block any kind of contents on AMO. Sticking to a dialog that pops up every other second and can easily break website functionality, is just not being realistic, Mozilla is still fighting for users privacy (tracking protection is a clear sign of that), but the tools used to do that should be on par with the current Web and should have the due quality, imo. {_{bug606655#c50} )

You may also be interested in this

• https://sporadicdispatches.blogspot.co.uk/2015/11/better-living-through-tracking.html

And the following addons

• Privacy Badger 1.8.1 https://addons.mozilla.org/firefox/addon/privacy-badger-firefox/
• Cookie Controller 5.5 https://addons.mozilla.org/firefox/addon/cookie-controller/
• uBlock Origin 1.9.6 https://addons.mozilla.org/firefox/addon/ublock-origin/
• Ghostery 6.3.2 https://addons.mozilla.org/en-GB/firefox/addon/ghostery

You are free to use an unsupported unsafe and insecure version of Firefox if you wish.

• Install an older version of Firefox

You may wish to mitigate risks by using a VM &/or having a well rehearsed bare metal restore policy.

• See also https://www.mozilla.org/security/known-vulnerabilities/firefox/

I went to the link "install an older version of Firefox". It doesn't tell me how to get the .exe that will install firefox 43. ???????????

I just installed "firefox setup 35.01.exe" on the computer in question. What I need is the corresponding 43 version. Where can I get it?????