Every so often AdBlock will disengage and notify "Waiting for data on port 2020". This is easy to fix, just go into WiFi or whatever and do the manual-localhost-2020-save routine. You may also need to go into AdBlock and switch it back on.

Always check notifications, the answer will be in there.

Adblock Plus allows some adverts through whereas Adblock Edge, which is an open source fork, lets none through.

I'd recommend uninstalling Adblock Plus and installinf Adblock Edge instead, which is available under Tools as an add-on.

I've been using Adblock Plus for a long time, and never yet had an ad get through. There is a switch for "Allow some non-obtrusive advertising", but that's turned off.

dd777. Thanks for the mention of Adblock Edge. I've had no bother on PPrune using Ad Blocker but lately I've been getting ads on BT/Yahoo mail, extremely intrusive.

Installed Edge in FF and now they've gone... :D