I know when I've clicked on a medium.com link because my CPU fan spins up chewing on all the framework junk.
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.
Also, do you have an NVMe or Optane SSD attached?
Lately been using teddit.net for browsing reddit and it’s been great.