Firefox use 35GB of RAM

I've checked the memory usage, and all the 30+ add-ons takes 400MB at peak performance, combined! That excludes the add-ons being the issue!

Why does https://cloudflare.com take 12 GIGABYTE? It jumps from 0-12GB continuously, and I don't even have any webpages open.

GPU also uses high amounts of RM, about 10GB.

This is not normal, it's a serious issue!

That sounds like some media/stream capability probe for fingerprinting :(( Have you checked it also reproduces in Troubleshoot Mode when any "privacy" addons are not tampering with the human verification services?

See if you have "Remote Improvements" enabled — as this can be another instance of bugzilla.mozilla.org/show_bug.cgi?id=2080876#c14

(That said, if the "clean browser with a single tab" is a wikipedia or example.net tab, is it the same, or your tab is something that contains bot protections or human checks?)

Thanks for the input, much appreciated. I blocked Cloudflare, which seem to have fixed the issue. When the process was cut, GPU also dropped from 10GB to 0.1GB. So in total, the RAM usage dropped from 19GB to 4.3GB (heavy browsing session).

It's a mystery to me why Cloudflare would warp up and down while using massive amounts of RAM and activating the GPU. A hung process or memory leak is usually fixed with a reboot.. Let's just hope it's not China listening in. = )

For the record if anyone else have this issue: uBlock - Open the dashboard(cog) - My filters - and add this line: ||challenges.cloudflare.com^ Apply changes and restart Firefox. It solved the issue for me momentarily, but it's probably a bad solution that will cause issues with lots of websites.