Sometimes you’ll see Anubis anti-bot checks to keep the site safe from spam and...

https://penelopessmartdigests.talesignal.com/posts/is-proof-of-work-bad-for-battery-life-on-laptops-and-phones

Sometimes you’ll see Anubis anti-bot checks to keep the site safe from spam and attacks. These checks use a Proof-of-Work test that runs in your browser with JavaScript