Firefox for Android works a little differently to other browsers, it manages its own certificates. So, in order to use Total Adblock in Firefox, you need to adjust a Firefox setting so that it trusts Total Adblock's certificate. 1. Open Firefox and tap the Firefox menu 2. Tap Settings, then scroll to the bottom and tap About Firefox 3. Rapidly tap the firefox logo several times, notifications will show once complete 4. Navigate back to Settings and tap a new option; Secret Settings 5. Toggle Use third party CA Certificates That's it! Firefox will now be ad free!