Updated in 2022, but I don't see anything on <Suspense> for example. That doesn't necessarily mean the info is now wrong, but it's definitely not complete anymore.
I did title it "_Mostly_ Complete Guide" for a reason :)
Everything in that post should still be 100% accurate and relevant.
I specifically did _not_ try to go into further details on Suspense or some of the intricacies of Concurrent Rendering (beyond "React can cancel or reset those render passes"). My overall goal was to explain the core mental model of how React's basic rendering works on the client side.
As far as Suspense goes, that can be summarized as "throw a promise while rendering, `<Suspense>` acts like a `try/catch` at the component level, React will re-render this component when the promise resolves and from its perspective that function call _always_ returned the data synchronously".
Concurrent Rendering is really complicated internally, but loosely: React has an internal notion of priorities for queued renders. `startTransition`, `useDeferredValue`, and Suspense all mark renders as low priority, so those render passes can be "rebased", interrupted, or canceled as needed based on updates that come in later.
