That's probably a PEBKAC in terms of your software choices or behaviour. Works fine for most users, you're a fringe case for whatever reason.
Everyone is a fringe case eventually. Even you.
If it is happening to the commenter continually throughout CF's network then I'd say that's probably their problem. Frequent or consistent? Well, it's probably the user.
Defending Firefox and adblock as a fringe case worthy of dismissal is a sad reflection of the current state of the internet.
VPN usage seems to be a common one as it's often shared with people who abuse it to attack others.