Ask HN: Does Collapsing an HN Thread in a Popular story spike your CPU use?

For popular threads with a lot of comments, collapsing a top comment leads to high CPU usage and can cause browsers (I tried in Chrome and Vivaldi) to freeze up.

For example, this very popular thread: https://news.ycombinator.com/item?id=43561253

If you collapse the top comment, I see a huge spike in CPU and my system freezes temporarily.

Is it just me?

The javascript that hides collapsed layers probably isn't optimized and doesn't scale up to thousands of DOM nodes well.

I have an old system with simple older firefox -- It can collapse the given example without even noticing ... well not perceptible to myself ... I'd call it near instantaneous, also tried repeatedly as well as going though collapsing the rest but was unable to cause a falter. I do though have a deny list of sites that provide / contain scripts that snoop too hard as well as a couple I'm suspected set up as resident in the background where the behaviour was only corrected with quit and restart. Mind that deny list results in a few innocent sites not loading up, but I can live with that.

Nope. I leave javascript turned off like with every other website. No CPU use issues.

Found the arch user ;-)