Can you post a screenshot of the issue and provide steps to replicate?

Not to hijack the thread, but I have the same issue I believe, and it is something that has been happening off and on with Firefox for years now. Previously it was discovered that there were other issues causing the endless DDoS pages including improper headers, but I am not at all surprised to hear that now it is this privacy option causing the problem.

One site I commonly use (fanfiction.net) is almost constantly leaving me on their "DDoS protection" page that is supposed to at worst last 5 seconds and only rarely be seen. But rather than being rare and short duration, for me it can last for several minutes before finally being allowed through and pops up almost every time I open a new page.

That site is not alone, merely the one I run into the issue most often on since I do a lot of browsing on it. Pretty much every website now that uses Cloudflare is giving me issues when I use the firefox browser. I include an image of the issue,, although sadly a picture alone can not show how long it persists or how common the issue is.

Not able to replicate the issue in Nightly or 93. see screenshot I also use Cloudflare for dns. Try downloading a separate copy of Firefox and run it from the folder(do not sign into you Firefox account) to see what happens.

https://www.mozilla.org/en-US/firefox/all/#product-desktop-release