What kind of Optimistic UI updates does Basecamp use?

What kind of Optimistic UI updates does Basecamp use?
We also know that basecamp uses Stimulus instead of those front-end frameworks having a virtual DOM or a state container like redux, flux or vuex. So how does it implement its Optimistic UI updates?

@sam @javan

I have looked at their UI. They don’t have any optimistic UI. You can turn off your internet and sort some Todos, it will work perfectly fine. But once you refresh the page, it will revert to its old state.

One feature I discovered by accident was that if your browser crashes or you close the tab accidentally while authoring new content (never saved), the next time you visit that URL, the previously written post will be restored. It was quite shocking and delightful to me.

Walter

I haven’t seen such thing. Although I am going to try it out.

Or may be that’s in case of rich text editing.