Why is collapsing a Hacker News comment so slow?
I would use the  tag to solve this problem. Most people don't know this exists and I have no idea why. You would probably have to rewrite the html so it no longer uses tables but I don't really consider that to be a negative.I would also question why we are saving collapsed comments. I feel like this is something that doesn't need to be persisted forever. If you want this behavior why not use local storage instead?