I know when I've clicked on a medium.com link because my CPU fan spins up chewing on all the framework junk.

In Firefox reddit (new version) will sit at about 50% of a core on my laptop. Simple mouse hover effects on the page lag about half a second behind my actual mouse cursor. YouTube (while not playing a video) will use about 15% of my cpu, even when idle in a background tab.

I’m not sure if the bug is in Firefox or in the sites, but it’s awful. I don’t understand how these issues don’t get fixed immediately. I thought for sure after the new reddit redesign landed that they’d iron out the performance issues in a month or two but I swear if anything it’s gotten worse.

It probably works fine on the developers' 32-core 96GB workstation, so could not reproduce, problem is on your end.

New Reddit is almost unusable for me in Safari as well, it amazes me how they are so popular when the experience in the browser is so bad. (old.reddit.com kinda works, but lots of embedded things like slideshows or videos are a really bad experience)

I have the exact same issues you’re describing - but only on my third monitor that’s attached to its own GPU. - I’m still investigating, but I think it’s a PCIe issue.

Also, do you have an NVMe or Optane SSD attached?

> In Firefox reddit (new version)

Lately been using teddit.net for browsing reddit and it’s been great.

Did you report it? You can use firefox profiler to learn what triggers CPU usage.

No, ads are a big problem too, let's not pretend they aren't a horrible blight. With that said, it is a bit ridiculous that webpages load MBs of JS (SPA-related or not), and that browsers load hundreds of MBs to JIT said Javascript...