Never encountered it once in thirteen years of using CloudFlare. If it did happen to me eventually as a one-off freak occurrence, that's a temporary fringe event.

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.

Happens to me too. And surely a bunch of others as well, who just don’t voice it.

Defending Firefox and adblock as a fringe case worthy of dismissal is a sad reflection of the current state of the internet.

I used Firefox and various ad blockers for years and never had any problems with CloudFlare.

VPN usage seems to be a common one as it's often shared with people who abuse it to attack others.

I have this problem, happens for perplexity.ai too for example... I never had issue until two months ago, and now I'm locked out of some quite interesting websites