Yeah - is such a large dom of essentially text expected to be that slow?

For what it's worth I use a small script that essentially deletes old chat messages DOM nodes which significantly speeds it up.

Yes, because under the hood it’s much more than just text. It’s not hard to imagine dozens if not hundreds of elements are contained within each prompt+reply pair.

I bet there’s also some React performance issues involved here too

There are some real table stakes FE perf issues with the ChatGPT site