We're on it and you can follow our progress in this issue
. Due to the holidays, there tend to be fewer resources available as usual but so far it looks like it's a Firefox bug so this may also affect other ad blockers.
@Cybo1927 I appreciate that you're helping out in this forum. In most cases, recommending other ad blockers doesn't resolve a user's problem because they're either affected by the same issue or it would have the same effect as simply reinstalling Adblock Plus. Furthermore, it prevents us from finding and fixing the problem for all our other users. Anything we find could also be helpful for browser makers - such as Firefox in this particular case - and even other ad blockers.
Therefore please refrain from doing so.